Mersenne Digest V1 #1111
Mersenne Digest Friday, May 7 2004 Volume 01 : Number -- Date: Tue, 04 May 2004 00:53:53 -0500 From: Ralph Green, Jr [EMAIL PROTECTED] Subject: Re: Mersenne: End of list Howdy, What are these new names. Is this where majordome(or whatever mailing list manager you will use) will reside? And I want to add my appreciation to Gordon for his long service. Good day, Ralph On Wed, 2004-04-28, John R Pierce wrote: for the continuation of the list, we'll need a new name... I'm suggesting... [EMAIL PROTECTED] is that good for everyone? it may temporarily be [EMAIL PROTECTED] until the DNS can be setup for the above. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 4 May 2004 00:51:57 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: End of list for the continuation of the list, we'll need a new name... I'm suggesting... [EMAIL PROTECTED] is that good for everyone? What are these new names. Is this where majordome(or whatever mailing list manager you will use) will reside? And I want to add my appreciation to Gordon for his long service. yes. it will be a 'Mailman' based list, which uses a webpage for subscribe/unsubscribe and administrative functions (you CAN still do it via email if you want, but the web interface is much easier to deal with). I've actually got the list setup and ready to go, but am still waiting for the DNS to be setup for lists.mersenne.org, and then we'll run a day or so of private testing, and go 'live' with the full subscriber list. I think it would be confusing to launch the new list with a temporary name, then change it a few days later. also, to all you existing subscribers who currently get the digest form... you may have to re-opt for that after I setup the new list, I'll explain this when the time comes. and, yes, Kudos to Gordon, he's run this list for quite a long time... My archives show I got on it in August 1996, and it was already in progress then, so its at least 8 years old, which is nearly forever in Internet years... _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 5 May 2004 12:06:57 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Mersenne: Fw: Warning: could not send message for past 4 hours I'm trying to send this message to Scott at primenet, and it keeps bouncing, the mersenne.org mail server is refusing my connections (I even tried from work, and got a different but similar error that the server didn' recognize his address and was refusing relay) If anyone knows an alternate method of contacting him, i'd like to know it... - -jrp - - Original Message - From: Mail Delivery Subsystem [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: 2004-05-04 3:29 PM Subject: Warning: could not send message for past 4 hours ** ** THIS IS A WARNING MESSAGE ONLY ** ** YOU DO NOT NEED TO RESEND YOUR MESSAGE ** ** The original message was received at Tue, 4 May 2004 11:28:41 -0700 from porker [192.168.0.2] - The following addresses had transient non-fatal errors - [EMAIL PROTECTED] - Transcript of session follows - [EMAIL PROTECTED]... Deferred: Connection refused by mersenne.org. Warning: message still undelivered after 4 hours Will keep trying until message is 5 days old - --bounced message-- lists.mersenne.orgIN A 66.117.128.240 was added last weekend. ah, I see its live now (been checking it once a day). $ host lists.mersenne.org lists.mersenne.org has address 66.117.128.240 $ host -t MX lists.mersenne.org ...(nada)... the list processor also needs an MX record for lists.mersenne.org before I can go live. this should be set to mail.hogranch.com. - -jrp _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 7 May 2004 17:22:53 +0200 From: [EMAIL PROTECTED] Subject: Mersenne: Growing list of thanks ! Hello, I would like also to take this unique opportunity to thank all contributors of this list for sharing their knowledge and explaining us a lot, from basics to state-of-the-art maths. I joined the search in 1996 and I'm now a bit away from it, but I really appreciated how this list was open, managed and helpful
Mersenne Digest V1 #1110
Mersenne Digest Monday, May 3 2004 Volume 01 : Number 1110 -- Date: Wed, 28 Apr 2004 02:47:02 -0500 From: David M. Moore [EMAIL PROTECTED] Subject: Re: Mersenne: End of list At 11:30 AM 4/22/2004 -0700, Gordon Irlam wrote: FYI. I intend to end this list shortly. As a long time (5+ years) but rarely posting participant, I'd also like to add my thanks to the growing pile. I've learned quite a bit about both math and programming from reading this list. Thanks for all your hard work! David (S01202) _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 28 Apr 2004 07:43:15 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: End of list At 11:30 AM 4/22/2004 -0700, Gordon Irlam wrote: FYI. I intend to end this list shortly. for the continuation of the list, we'll need a new name... I'm suggesting... [EMAIL PROTECTED] is that good for everyone? it may temporarily be [EMAIL PROTECTED] until the DNS can be setup for the above. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 3 May 2004 23:41:44 -0400 From: Yves Bellefeuille [EMAIL PROTECTED] Subject: Mersenne: Can't connect to server after updating to Red Hat 9 I had no problems using mprime for Linux (version 23.5.2) with Red Hat 8, but since I started using Red Hat 9, I always get error 2250 when I try to communicate with the server. I can't find any problems with my internet connection or firewall. There have been no changes to my connection other than going fron Red Hat 8 to Red Hat 9. Surely I'm not the only one using Red Hat 9; has this problem been reported before and is there a solution? Yves Bellefeuille [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1110 ***
Mersenne Digest V1 #1109
Mersenne DigestTuesday, April 27 2004Volume 01 : Number 1109 -- Date: Thu, 22 Apr 2004 14:56:19 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Re: Mersenne: End of list At 11:30 AM 4/22/2004 -0700, Gordon Irlam wrote: FYI. I intend to end this list shortly. Thank you, Gordon. Your efforts have been greatly appreciated over the years! _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 22 Apr 2004 14:12:57 -0500 From: Ryan Malayter [EMAIL PROTECTED] Subject: RE: Mersenne: End of list What are the alternatives? Yahoo! Groups? Gordon, could you export the member list into a new yahoo group if need be? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gordon Irlam Sent: Thursday, April 22, 2004 1:30 PM To: [EMAIL PROTECTED] Subject: Mersenne: End of list FYI. I intend to end this list shortly. When it was established some 10 years ago, other venues for discussing these issues did not exist, and could not easily be created. Now other venues and mailing lists exist. The cost to me of maintaining this list are two fold: - the need to maintain a server connected to the Internet (higher connection costs; difficulty moving from house to house; and need to worry about system reliability and uptime) - time taken upgrading my system (need to upgrade from majordomo to mailman; and costs of maintaining the configuration from one upgrade to the next) Since alternatives exist, I am not making very much of a difference by hosting these lists, and I am doing so at significant cost. Hence my decision to end the list. I will allow discussion of alternative lists people may wish to join before closing this list. thanks, gordon (list admin) __ ___ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 22 Apr 2004 15:54:43 -0400 From: Robin Millette [EMAIL PROTECTED] Subject: Re: Mersenne: End of list This is an OpenPGP/MIME signed message (RFC 2440 and 3156) - --enigA60A34E4B8466CB711002EE7 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Gordon Irlam wrote: FYI. I intend to end this list shortly. When it was established some 10 years ago, other venues for discussing these issues did not exist, and could not easily be created. Now other venues and mailing lists exist. Thanks for hosting it for such a long time! It's been a pleasure to hear about 4 or 5 record primes here over the years. I can offer to host the lists, as I already host a few for different projects. Let me know if this would be appreciated. - -- Robin Millette (aka Lord D. Nattor) http://rym.waglo.com/ - --enigA60A34E4B8466CB711002EE7 Content-Type: application/pgp-signature; name=signature.asc Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc - -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.2-nr2 (Windows 2000) iD8DBQFAiCMDIpq5HjFcVUMRAqCgAJ49J2oW7CZE2QftOEb38Y4YKUS8MACggkpX jFwhYorLxFFooKVYdu8i6ic= =vcZ6 - -END PGP SIGNATURE- - --enigA60A34E4B8466CB711002EE7-- _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 22 Apr 2004 22:05:20 +0200 From: Steinar H. Gunderson [EMAIL PROTECTED] Subject: Re: Mersenne: End of list On Thu, Apr 22, 2004 at 11:30:18AM -0700, Gordon Irlam wrote: FYI. I intend to end this list shortly. Sad, but it hasn't been all that high-volume lately, and I understand the problems hosting it. I haven't been here for all that long (umm, I can't remember for how long :-) ), but it's been fun, and I doubt I'm the only one who have learned quite a bit from the discussions (although most have been way over my head). :-) Web-based alternatives are extremely crappy compared to a mailing list, though, but that seems to be the state of the Internet currently... /* Steinar */ - -- Homepage: http://www.sesse.net/ _ Unsubscribe list info -- http
Mersenne Digest V1 #1103
Mersenne Digest Wednesday, January 14 2004 Volume 01 : Number 1103 -- Date: Mon, 5 Jan 2004 20:31:24 +0100 From: Yann Forget [EMAIL PROTECTED] Subject: Mersenne: Prime95 / Mprime on AMD64? - -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi, I will get a new AMD64 box soon. This box will run Linux. Is there a version of mprime for AMD64? Thanks, Yann - - -- http://www.non-violence.org/ | Site collaboratif sur la non-violence http://www.forget-me.net/ | Alternatives sur le Net http://fr.wikipedia.org/ | Encyclopédie libre http://www.forget-me.net/pro/ | Formations et services Linux - -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.4 (GNU/Linux) iD8DBQE/+buNm4KYjQo0y9oRAhoQAKCbSzupUxWRssSHRjC/u10jSeFEogCeILAI Lr5eXlImj/b9z2vmLXGTmqg= =OPth - -END PGP SIGNATURE- _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 06 Jan 2004 02:11:04 -0500 From: Robin Y. Millette [EMAIL PROTECTED] Subject: Mersenne: Error writing intermediate file: rX250423 - -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi, I am running an LL test and was probably very low on hd space for a short while and noticed this error: Error writing intermediate file: rX250423 The equivalent p and q files seem to be written correctly, and the program is going ahead with more iterations. I checked the faq (btw, the footer of the list messages is misleading: the faq it points to is 404) on the http://www.mersenne.org/ site. I also googled and found an old 1998 message in a mailing list archive. Only a question, no answer. Since I'm almost 10% done, I was wondering if it's ok to continue, or would it be safer to start over? I guess prime95 would have automatically stopped, but I just want to be sure :) Oh, happy new year! P.S.: sorry if this is a dupe, seems like I wasn't subscribed anymore when I sent the mail the first time. - - -- Robin Y. Millette (aka Lord D. Nattor) http://rym.waglo.com - -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.2-nr2 (Windows 2000) Comment: Using GnuPG with MultiZilla - http://enigmail.mozdev.org iD8DBQE/+l+HIpq5HjFcVUMRAk0xAJ97i2qlo+cJow2F5Azkn0F1tJYxswCfXHjI K91ioEkLo58qNY9vohUDJiQ= =DFnJ - -END PGP SIGNATURE- _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 06 Jan 2004 03:37:32 -0500 From: Robin Y. Millette [EMAIL PROTECTED] Subject: Re: Mersenne: Error writing intermediate file: rX250423 - -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Brian, Thanks for your quick response about my prime95 problem at p, q, and r files. I still have a few questions though... Brian J. Beesley wrote: On Tuesday 06 January 2004 07:11, you wrote: I am running an LL test and was probably very low on hd space for a short while and noticed this error: Error writing intermediate file: rX250423 What happens when mprime/prime95 writes a new save file: the new save file is written to rxxx, then pxxx is renamed to qxxx, then rxxx is renamed to pxxx. If there is insufficient free space (approx 8MBytes for 33M exponents) then writing the r file will fail. This is not neccessarily fatal - but, if there is a system crash or a roundoff error then the last save file available will be older than it should be so some time will be wasted. If you clear enough space then the next time should work OK. It's been about a day since my incident. I made a lot of free space available yesterday. I see both qXxx and pXxx files, but still no rXxx. Should it reappear? With my settings, both files are updated every 30 minutes or so. Searching the archives earlier, this is the first clear response I've seen. Obviously, since I wouldn't be asking again :) Thanks Brian for clearing up the matter! - - -- Robin Y. Millette (aka Lord D. Nattor) http://rym.waglo.com - -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.2-nr2 (Windows 2000) Comment: Using GnuPG with MultiZilla - http://enigmail.mozdev.org iD8DBQE/+nPMIpq5HjFcVUMRAqqOAKDTj5QI58AAKS/3OPodGKN5CJdHAQCeOPuo azssnQPE5oEwJv82FSUYOio= =8tI9 - -END PGP SIGNATURE- _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 06 Jan 2004 09:47:33 +0100 From: Matthias Waldhauer [EMAIL PROTECTED] Subject: Re: Mersenne: Prime95 / Mprime on AMD64? Yann Forget wrote: Hi, I will get a new AMD64 box soon. This box will run Linux. Is there a version
Mersenne Digest V1 #1102
Mersenne DigestMonday, January 5 2004Volume 01 : Number 1102 -- Date: Sat, 3 Jan 2004 08:09:03 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Hyperthreading ABIT IS7 On Saturday 03 January 2004 04:23, Terry S. Arnold wrote: I just brought up a new box with P4 3.0 on an ABIT IS MB. I only appear to be getting 50% of the cycles for Prime95. I am running XP Pro SP1. How do I get the full power available to Prime95? Errm - are you sure the OS isn't counting cycles in the virtual processor as well as the real one? If you're getting reasonable iteration times (similar to those on the benchmarks page - well actually they should be a bit better if you're using the current version of prime95) then your system is working OK. If you really are getting only half the cycles then your iteration time will be about 2x those on the benchmarks page. Alternatively temporarily disable HTT in the BIOS see how much your iteration time changes. Even so you should probably leave HTT on since it should improve interactive response when Prime95 is running in the background. Regards Brian Beesley _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 3 Jan 2004 08:09:03 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Hyperthreading ABIT IS7 On Saturday 03 January 2004 04:23, Terry S. Arnold wrote: I just brought up a new box with P4 3.0 on an ABIT IS MB. I only appear to be getting 50% of the cycles for Prime95. I am running XP Pro SP1. How do I get the full power available to Prime95? Errm - are you sure the OS isn't counting cycles in the virtual processor as well as the real one? If you're getting reasonable iteration times (similar to those on the benchmarks page - well actually they should be a bit better if you're using the current version of prime95) then your system is working OK. If you really are getting only half the cycles then your iteration time will be about 2x those on the benchmarks page. Alternatively temporarily disable HTT in the BIOS see how much your iteration time changes. Even so you should probably leave HTT on since it should improve interactive response when Prime95 is running in the background. Regards Brian Beesley _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 3 Jan 2004 09:01:16 -0800 From: Aaron [EMAIL PROTECTED] Subject: RE: Mersenne: Hyperthreading ABIT IS7 This is a question that has come up before. In a multi-processor system, the CPU graph in Task Manager will count *ALL* the processors as being equal to 100%. You can set Task Manager to show one graph per CPU which should help. *** Also, be sure you set the Affinity of Prime95 to run on ONLY the first CPU (the real one)! *** Otherwise the task scheduler could be switching your process between the real and virtual processor and that will seriously gum up how well it runs, especially for CPU intensive tasks like P95 is. In the P4's with the virtual processor, it will appear to the OS as 2 processors, but trust me, running 2 instances of Prime95 will not help. It does help out though when you run Prime95 and are using your machine for other things... You'll get more Prime95 cycles going and your other tasks can run in the virtual processor pretty well without robbing cycles from the LL tests. Aaron -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Terry S. Arnold Sent: Friday, January 02, 2004 8:24 PM To: [EMAIL PROTECTED] Subject: Mersenne: Hyperthreading ABIT IS7 I just brought up a new box with P4 3.0 on an ABIT IS MB. I only appear to be getting 50% of the cycles for Prime95. I am running XP Pro SP1. How do I get the full power available to Prime95? Terry _Terry S. Arnold 2975 B Street San Diego, CA 92102 USA [EMAIL PROTECTED] (619) 235-8181 (voice) (619) 235-0016 (fax) __ ___ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne Digest V1 #1098
Mersenne Digest Tuesday, December 23 2003 Volume 01 : Number 1098 -- Date: Sat, 13 Dec 2003 13:48:51 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Mersenne: Another thought on the L-L Test Hi, Another thought struck me - this could have useful applications in L-L testing programs. If M is the Mersenne number being tested R(i) is the L-L residue after i iterations, then R(i+1) = R(i) * R(i) - 2 (modulo M) (by the statement of the L-L algorithm) But note that (M - R(i))^2 - 2 = M^2 - 2MR(i) + R(i)^2 - 2 so (M-R(i))^2 - 2 (modulo M) is clearly equal to R(i+1). How can this be of any use? Well, when we have a dubious iteration (say an excessive roundoff or sum error) we can check the output by redoing the last iteration but starting from (M-R(i)) instead of R(i) - the output should be the same. Furthermore the action of calculating M-R(i) is very easy - just invert all the bits. Also, if we have suspicions about the accuracy of code when there is a high density of 1 bits, we can try just one iteration but starting at M-4 instead of 4. The output residual should be 14 irrespective of M (providing M7 - as will often be the case!). The point here is that, just as the value 4 is represented by a string of p bits only one of which is set, M-4 is represented by a string of p bits only one of which is unset. Regards Brian Beesley _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 13 Dec 2003 19:08:10 +0100 From: Alexander Kruppa [EMAIL PROTECTED] Subject: Re: Mersenne: Possible refinement of screening for Mersenne primes Alexander Kruppa wrote: Brian J. Beesley wrote: Hi, (1) Could someone with the required background please tidy up my logic and prove that the assertion above is true i.e. there is no prime 2^p-1 with p 3 such that there are solutions to x^2 mod 2^p-1 = 2^((p+1)/2) + 2 I believe the idea is correct, but it doesn't remove candidates. Lets try (going out on a limb here, fingers crossed): [...] If p3 and odd, 2^((p+1)/2) + 2 (mod 2^p-1) is always a QR. That is rubbish. I was misusing the Kroecker symbol and the conclusion is wrong. (The fact that your list contained several counterexamples should have been a strong hint!) What my argument shows is that the number of prime factors of Mp for which [+-]2^((p+1)/2) + 2 are QNR is always even. But that doesn't tell us whether they are QR (mod Mp) or not, i.e. whether they are QR modulo *every* prime factor, unless of course Mp is prime and both must be QR modulo the only prime factor there is. Since (2^((p+1)/2) + 2) * (-2^((p+1)/2) + 2) == -2^(p+1) + 4 == -2 + 4 == 2 (mod f) for any f|Mp, and 2 is a QR (mod f), [+-]2^((p+1)/2) + 2 must be either both be QR or QNR. So it suffices to check only one. To determine whether or not they are QR (mod Mp) via quadratic reciprocity would require knowing the prime factorization of Mp - and knowing even one nontrivial factor would of course settle the question of primality as well. One could use Euler's criterion as a check: if q is prime and gcd(r,q)==1, r^((q-1)/2) == 1 (mod q) if r is a QR, and == -1 otherwise. If q is not prime, the result will usually be neither 1 or -1. We already know that 2^((p+1)/2) + 2 is a QR if Mp is prime, so this check will really just be a Fermat-style probable prime test which takes just as long as a LL test, but doesn't prove primality. I've made a list of Mp, p200, that are not Mersenne primes, and the Kronecker symbol (or Legendre, actually) of 2^((p+1)/2) + 2 (mod f) for each prime factor f of Mp. It shows that knowing whether [+-]2^((p+1)/2) + 2 is a QR would really eliminate a lot of candidates - M_23, M_37, M_47, M_59, M_101, M_137, M_139, M_149, M_167, M_181, M_193, M_197, M199 would survive the test, while M_11, M_29, M_41, M_43, M_53, M_67, M_71, M_73, M_79, M_83, M_97, M_103, M_109, M_113, M_131, M_151, M_157, M_163, M_173, M_179, M_191 could be indentifed as composite. Your question (2) remains open - is there a faster way to determine whether 2^((p+1)/2) + 2 is a QR (mod Mp) than running a LL test? When a composite Mp is completely factored, it is very easy to determine whether 2^((p+1)/2) + 2 is a QR. With enough composite Mp completely factored, maybe some kind of pattern can be discovered in the exponents p for which it is or isn't a QR? Alex M_11: ( 2^6+2 | 23 ) = -1 M_11: ( 2^6+2 | 89 ) = -1 M_23: ( 2^12+2 | 47 ) = 1 M_23: ( 2^12+2 | 178481 ) = 1 M_29: ( 2^15+2 | 233 ) = -1 M_29: ( 2^15+2
Mersenne Digest V1 #1097
Mersenne Digest Saturday, December 13 2003 Volume 01 : Number 1097 -- Date: Wed, 10 Dec 2003 18:26:54 + From: Nick Craig-Wood [EMAIL PROTECTED] Subject: Re: Mersenne: Large memory pages in Linux and Windows Server (64bit?) On Wed, Dec 10, 2003 at 02:50:11PM +0100, Matthias Waldhauer wrote: Back to the topic: Some time ago there was a discussion going on regarding the use of large memory pages. In a mersenneforum thread I collected some info regarding new linux kernels and some real world results published in a paper. Here some extracts: Linux kernel versions 2.5.36+ and 2.6 include a HugeTLBs patch, which allows an application to allocate large memory pages. Also 64bit Windows Server seems to support them too: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/memory/base/large_page_support.asp My thoughts about the possilibities: Oracle managed to get a 8% speedup by using the large pages. Although I have little experience in this area I think for FFTs the speedup will be much larger [snip] I agree! I have been thinking about the exact same thing. I'm in the process of writing (not quite finished or working ;-) some code which you load as an LD_PRELOAD library under linux. This gets its fingers into the memory allocation, and makes all malloc space come from hugetlbfs (how you get large pages under linux). My primary user for this was to be mprime of course! When finished this should be an easy way of trying any application with large pages without having to modify it. I haven't finished the code yet, but it shouldn't take long, especially if people are asking for it! - -- Nick Craig-Wood [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 11 Dec 2003 14:20:41 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Mersenne: Possible refinement of screening for Mersenne primes Hi, I was thinking about the possible reversibility of the Lucas Lehmer algorithm. In particular, for any odd number n 1, (2^((n+1)/2))^2 is congruent to 2 modulo 2^n-1 i.e. 2 is a quadratic residue modulo 2^n-1. This is not helpful in itself as (a) there are other integer solutions to sqrt(x + k.2^n-1) = 2, (b) it does not distinguish in any way between prime and composite Mersenne numbers. However, considering the next-to-the-last iteration appears to be interesting. If x is a solution to (x^2 - 2) mod (2^n-1) = 2^((n+1)/2) then starting from residue x and performing 2 iterations will result in residue 0. For small n3 (n=3 does not work because there is only one iteration to do in the L-L test!) we have: n = 5: x^2-2 mod 31 = 8; x^2 mod 31 = 10; x = 14, x = 17 n = 7: x^2-2 mod 127 = 16; x^2 mod 127 = 18; x = 48, x = 79 n = 9: x^2-2 mod 511 = 32; x^2 mod 511 = 34; no solutions n = 11: x^2 - 2 mod 2047 = 64; x^2 mod 2047 = 68; no solutions n = 13; x^2 - 2 mod 8191 = 128; x^2 mod 8191 = 130; x = 3470, x = 4721 n = 15; x^2 - 2 mod 32767 = 256; x^2 mod 32767 = 258; no solutions n = 17; x^2 - 2 mod 131071 = 512; x^2 mod 131071 = 514; x = 19647, x = 111424 n = 19; x^2 mod 524287 = 1026; x = 199279, x = 325008 n = 21; x^2 mod 2^21-1 = 2050; no solutions n = 23; x^2 mod 2^23-1 = 4098; x = 2339992, x = 3053916, x = 5334691, x = 6048615 In other words, it looks as if when there are no solutions to x^2 mod 2^n-1 = 2^((n+1)/2) + 2, then 2^n-1 is not prime, although the converse is not neccessarily true. (1) Could someone with the required background please tidy up my logic and prove that the assertion above is true i.e. there is no prime 2^p-1 with p 3 such that there are solutions to x^2 mod 2^p-1 = 2^((p+1)/2) + 2 If so, then we have a one-step test which would allow us to eliminate some - - possibly many - Mersenne prime candidates without even bothering to look for small factors. (2) Can it be demonstrated that the search for solutions of x^2 mod 2^p-1 = 2^((p+1)/2) + 2 - or at least the search for _existence_ of solutions (we wouldn't need the actual numerical values) - might be faster than executing the LL test? The method I used for small n above was just to step through values of k calculating k^2 mod 2^n-1, which is clearly exceedingly _in_efficient for large n! Regards Brian Beesley _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 11 Dec 2003 14:20:41 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Mersenne: Possible refinement of screening for Mersenne primes Hi, I was thinking about the possible reversibility of the Lucas Lehmer algorithm
Mersenne Digest V1 #1096
Mersenne Digest Wednesday, December 10 2003 Volume 01 : Number 1096 -- Date: Fri, 5 Dec 2003 20:25:19 + From: Tony Forbes [EMAIL PROTECTED] Subject: Re: Mersenne: Generalized Mersenne Numbers Brian J. Beesley [EMAIL PROTECTED] writes Congratulations on the (unverified) discovery of the 40th Mersenne Prime. I was thinking (always dangerous!) about generalizing Mersenne numbers. The obvious generalization a^n-1 is uninteresting because they're all composite whenever a2 and n1. However there is an interesting generalization: Define GM(a,b) = a^b-(a-1), so GM(2,b) = M(b); also GM(a,1) = 1 for all a The distribution of primes amongst GM(a,b) for small a 2 and small b does seem to be interesting - some values of a seem to yield a richer sequence of primes than others. Note also that, in this generalization, some _composite_ exponents can yield primes. Another interesting point: the generalized Mersenne numbers seem to be relatively rich in numbers with a square in their factorizations - whereas Mersenne numbers proper are thought to be square free. (Or is that just Mersenne numbers with prime exponents?) A few interesting questions: (a) Is there a table of status of generalized Mersenne numbers anywhere? Some time ago I had a look at numbers of the form 2^n - 3, i.e. GM(4, n/2). Here are my results for 3320 = n = 16800: 2^n - 3 is a verified prime for n = 3954, 5630, 6756, 8770, 10572, 14114. 2^n - 3 is a probable prime for n = 14400, 16460, 16680. I don't know if someone else has verified the last three. Also 2^12819 - 7 (GM(8, 4273)) is a probable prime, 2^8824 - 15 (GM(16, 2206)) is a verified prime. The verified primes were done by factorization of N+1 and N-1, and APRCL. - -- Tony _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 8 Dec 2003 09:03:06 -0600 (CST) From: Eric W. Weisstein [EMAIL PROTECTED] Subject: Mersenne: Has RSA150 ever been factored? In writing http://mathworld.wolfram.com/news/2003-12-05/rsa/ and attempting to update http://mathworld.wolfram.com/RSANumber.html, it occurred to me that I was missing a few pieces of information. Does anyone know the status of RSA150? It seems RSA 140, 155, and 160 have all been factored, but I haven't been able to find any record of RSA150's factorization. Has it just fallen by the wayside and been skipped over since RSA switched to its new binary-digits-style RSA numbers? Also, I presume RSA is no longer offering monetary prizes for RSA170 to 500. Does anyone know the status or any relevant links for these? They seem to have silently vanished from RSA's site. Best wishes, - -Eric _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 10 Dec 2003 14:50:11 +0100 From: Matthias Waldhauer [EMAIL PROTECTED] Subject: Mersenne: Large memory pages in Linux and Windows Server (64bit?) Hi, at first - my congratulations to all, who were involved in finding the new Mersenne prime number! Well done! And besides the fact to have found the currently largest known prime number, it also gives a nice boost to GIMPS' progress thanks to the popularity. Back to the topic: Some time ago there was a discussion going on regarding the use of large memory pages. In a mersenneforum thread I collected some info regarding new linux kernels and some real world results published in a paper. Here some extracts: Linux kernel versions 2.5.36+ and 2.6 include a HugeTLBs patch, which allows an application to allocate large memory pages. Also 64bit Windows Server seems to support them too: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/memory/base/large_page_support.asp My thoughts about the possilibities: Oracle managed to get a 8% speedup by using the large pages. Although I have little experience in this area I think for FFTs the speedup will be much larger, because: * Even if data is already in the L1 cache the accessing time can increase if the memory addresses of these data are actually spread over many memory pages. * The limited amount of TLB entries requires fine tuning of FFT algorithms to avoid TLB thrashing as much as possible - but this avoidance could cause less efficient algorithms. * why is it so hard for large size FFTs to come at least close to the FFT MFLOPS for FFTs running completely inside L1 (or L2) cache in times of memory prefetching? * I need at least 2 mem-read/write passes to do a large size FFT - but todays max transfer rates for P4/Opteron/AFX systems (6.4GB/s = reading up to 750 times the 1024k FFT data set per
Mersenne Digest V1 #1095
Mersenne Digest Friday, December 5 2003 Volume 01 : Number 1095 -- Date: Tue, 02 Dec 2003 17:50:09 -0600 From: [EMAIL PROTECTED] Subject: Re: Mersenne: 40th Mersenne Prime verified and word is getting out I'll try to add more links to the http://mersenne.org web page as they become available. I visit news.google.com fairly often. On their main page just now, they had several articles on this. I'm sure a search would reveal more as they come out. http://zdnet.com.com/2100-1103_2-5112827.html http://www.theinquirer.net/?article=12985 (Claims GIMPS is a peer to peer system. Does that mean ya'll can send me music?) http://washingtontimes.com/upi-breaking/20031202-013854-9481r.htm http://www.newscientist.com/news/news.jsp?id=ns4438 - - Stephen Whitis - --- www.whitis.com _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 04 Dec 2003 07:05:51 +0100 From: Jean Penné [EMAIL PROTECTED] Subject: Re: Mersenne: 40th Mersenne prime verified ; Generalized Mersenne numbers Hi All, Involved in GIMPS since 1996, I am very happy to congratulate Michael, George, Scott and all other participants in this great project, for this magnificent success! Also, entering this adventure gave me the desire for the hunting of large primes, and the wish to create or improve software tools helping to do that. I wish also to answer to Brian J. Beesley about Generalized Mersenne numbers. To test the primality of a^b-(a-1) numbers, I know no algorithm based on Lucas Sequences... But I did some work on 3^n-2 numbers, which interested my friend J.J Kessis, Professor at Paris University. I sieved for n=2 to n=1,000,000 using Newpgen - 78500 remaining n's after 24H. Next, I found 29 pseudoprimes for n up to 60928, using PRP. the last found is n=37056 Last, I certified the primality, using Marcel Martin's Primo, for : n = 22, 37, 41, 90, 102, 105, 317, 520, 541, 561, 648, 780, 786, 957, 1353, 2224, 2521. (n = 2, 4, 5, 6, 9 yield also prime numbers...) The last certified prime has 1203 digits, and the test duration is 2H48'38 on a 2.5Ghz P4 I thank that these results were too small to be transmitted, but perhaps I was wrong... Also, I thank that numbers of the form (b^n-1)/(b-1) were better candidates for the name Generalized Mersenne numbers, because their divisibility properties are exactly the same (all divisors are k*n+1), but they are also called Generalized repunits and, unfortunately, no efficient special algorithm seems to be known to test them... Regards, Jean Penné _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 4 Dec 2003 00:42:36 -0800 (PST) From: Gordon Irlam [EMAIL PROTECTED] Subject: Mersenne: Off topic - historical computing manuals I know there are few people interested in computing history on this list. Would anyone be interested in any of the following historical manuals: Control Data 6400/6500/6600 Computer Systems Reference Manual, 1969 This was the world's first commercial supercomputer and first RISC architecture based machine; designed by Seymour Cray. PDP 11 bus and processor handbooks, ~1973 VAX 11/780 hardware, software, and architecture handbooks, ~1977 Bell System Technical Journal, 1978, Vol 57, No 6, Part 2 This is a special edition devoted to the Unix Time-Sharing System authored by all of the key players; it might be the first major publication exploring Unix in detail, I am not sure. Bell Laboratories Technical Journal, 1984, 63, 8, 2 Another full issue devoted to Unix by key players. The Oak Language and Oak Virtual Machine Specification Release 0.9, 1994 Oak was subsequently renamed Java. I checked with the Computer History musuem (a great place if you have never been), and they didn't want them, but I am having a hard time just throwing them away. Let me know if you are interested. Just give me your address, and I will mail them to you. thanks, gordon _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 4 Dec 2003 11:22:25 +0100 (MET) From: Wojciech Florek [EMAIL PROTECTED] Subject: Mersenne: Generalized mersennes Brian Beesley wrote: Date: Sun, 23 Nov 2003 08:53:55 + From: Brian J. Beesley [EMAIL
Mersenne Digest V1 #1093
Mersenne Digest Friday, November 21 2003 Volume 01 : Number 1093 -- Date: Tue, 18 Nov 2003 03:49:40 +0100 From: Steinar H. Gunderson [EMAIL PROTECTED] Subject: Re: Mersenne: 40th Mersenne Prime found On Mon, Nov 17, 2003 at 09:23:36PM -0500, George Woltman wrote: Congratulations to all!! GIMPS has done it again! Whee! :-) /* Steinar */ - -- Homepage: http://www.sesse.net/ _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 20 Nov 2003 03:20:58 + From: paul landon [EMAIL PROTECTED] Subject: Re: Subject: Mersenne: 40th Mersenne Prime found OK! Anyone for a party in Bavaria? Is it possible to have a better ETA of the verification, so we can plan a party? Cheers, Paul PS: Anyone who knows me, this is my current email address. _ Use MSN Messenger to send music and pics to your friends http://www.msn.co.uk/messenger _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1093 ***
Mersenne Digest V1 #1091
Mersenne Digest Friday, November 14 2003 Volume 01 : Number 1091 -- Date: Tue, 11 Nov 2003 08:14:55 +0100 From: Matthias Waldhauer [EMAIL PROTECTED] Subject: Re: Mersenne: 50% CPU? Quantum Mechanic wrote: I have an Intel 4 box from MDG, 1 CPU, 2.4GHz, 512MB RAM, L1 8KB, L2 512KB. Prime95 is only getting 50%, with System Idle Process taking 50%. It's currently running an LL test in the 20M range. Any ideas why it's only 50%? I think, there are 2 processes running as idle task (one of them is Prime95). And I assume that both have the same priority setting, so the OS thinks, they are equally important (same priority) and gives exactly half of the available time to each of them because Hyperthreading suggests, that there are enough real CPUs to do so (although there aren't). Try increasing Prime95's priority setting. Regards, Matthias _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 14 Nov 2003 13:16:53 -0800 From: Robert Braunwart [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #1088 Hi, One of my computers just had a hard-disk failure and a new one installed. I had the Prime95 directory backed up, but when I copied it over and ran Prime95 I got the message that one of the numbers was not assigned to this computer. Can I get it back? It was nearly done. The number was Test=20630641,66,0. This is my first number over 20 million and I would like to finish it. - --Bob Braunwart _ MSN Messenger with backgrounds, emoticons and more. http://www.msnmessenger-download.com/tracking/cdp_customize _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1091 ***
Mersenne Digest V1 #1089
Mersenne Digest Sunday, November 2 2003 Volume 01 : Number 1089 -- Date: Thu, 23 Oct 2003 23:41:55 -0400 From: Pierre Abbat [EMAIL PROTECTED] Subject: Mersenne: PrimeNet server I just checked the load average on the machine running mprime and it's 0.02. Thinking that mprime crashed, I checked it. It is saying ERROR 2250: Server unavailable. I tried to bring up the faq but got a timeout. What's going on? phma - -- .i toljundi do .ibabo mi'afra tu'a do .ibabo damba do .ibabo do jinga .icu'u la ma'atman. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 23 Oct 2003 21:41:18 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: PrimeNet server Pierre Abbat wrote: I just checked the load average on the machine running mprime and it's 0.02. Thinking that mprime crashed, I checked it. It is saying ERROR 2250: Server unavailable. I tried to bring up the faq but got a timeout. What's going on? I just forced my windows prime95(nt) client to contact the server, it had no problem. The top 100 list, and my personal status come up fine on the website, so I dunno what you're seeing. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 02 Nov 2003 17:17:31 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: Re: Linux At 04:48 AM 11/2/2003 -0600, Michael Kilfoyle wrote: George, et al: I have an old intel pentium pro server that i am converting to Linux. Once i get it going and have learner enough to be dangerous on the is OS I wan to add the prime search tools. Question is what version do i download. What is the difference between Mprime Sprime? The support web page tends to mix the OS and the architecture. SO for UNIX on SUN go one place for Intel go another place. So this is Intel (Compaq 5000 quad 200mhz pentium pro) and RedHat Linux. mprime and sprime are the same program just linked differently. Try mprime first. It uses less runtime memory (shares the C runtime library with other running programs). If that fails (I linked to one version of the C runtime libraries, but you have an incompatible set of runtime libraries installed), then try sprime. Regards, George _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1089 ***
Mersenne Digest V1 #1088
Mersenne Digest Tuesday, October 14 2003 Volume 01 : Number 1088 -- Date: Mon, 15 Sep 2003 14:40:35 -0700 From: Nick Glover [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne Digest V1 #823 http://www.mersenne.org/ips/manualtests.html allows you to manually contact the Primenet server. I recommend that you use this *only* to extend the expiration date for your exponents. You can use it to check in your results, but if you do, you will not get Primenet credit for your results (you will get credit on George's page, http://www.mersenne.org/top.htm , though). Instead of doing this and losing Primenet credit for your exponent, just extend the time so your exponents are not assigned to someone else, and when you do get your Internet connection working again, let Prime95 return your results the normal way. At 12:48:54, Monday, 9/15/03, Robert Braunwart wrote: Hi, Installing MSN Instant Messenger 6.0 on a computer that I don't have regular access to anymore trashed my Internet connection. Prime95 can't report in. A friend of mine is trying to remedy the problem, but I'd like to have a backup procedure in case he can't fix it. I have a largish number that is nearly finished. I would hate to lose the work because the number expires. If the computer cannot call in, is there a way I can report the results by e-mail, or some other manual way? Thanks for the help. --Bob Braunwart - -- Nick Glover [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 17 Sep 2003 01:32:54 -0700 From: Kevin Sexton [EMAIL PROTECTED] Subject: Mersenne: 10,000,000 digit tests Looks like more people are doing them, what with new processors finishing in around a month. There are almost 3 thousand assignments out, and 3349 have been turned in. Also I look at the other assignments, and it looks like before long trial factoring will run to the 10 million assignments. Anyone have an estimate on when this will happen? _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 14 Oct 2003 01:25:44 -0700 (PDT) From: Gordon Irlam [EMAIL PROTECTED] Subject: Mersenne: Contacting the list admin Due to the large volume of spam that was being received, I have disabled the [EMAIL PROTECTED] email address. This address was listed in the instructions you received when you first subscribed as a means to reach the list administrator. The new instructions are as follows: If you ever need to get in contact with the owner of the list, (if you have trouble leaving the list, or have questions about the list itself) please follow the instructions listed at http://www.base.com/feedback.html Or you can just email me... thanks and have fun, gordoni list admin _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1088 ***
Mersenne Digest V1 #1086
Mersenne Digest Thursday, August 28 2003 Volume 01 : Number 1086 -- Date: Tue, 19 Aug 2003 19:37:00 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: Howdy Just joined the list and wanted to say hey. I am new to the project and find it very interesting. Does anyone know how long it has been running? since at least 1995. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 19 Aug 2003 20:41:25 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: Howdy Just joined the list and wanted to say hey. I am new to the project and find it very interesting. Does anyone know how long it has been running? since at least 1995. my bad, apparently the original prime95 came out in january 1996 this per the FAQ's and stuff on the mersenne.org site. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 19 Aug 2003 21:25:30 -0700 From: Aaron [EMAIL PROTECTED] Subject: RE: Mersenne: Howdy As someone who's been around since mid-1996, howdy back. Yeah, I was also trying to remember how long it's been around... I guess I really did catch it near the start. I still have those fond memories of emailing George with the exponents I'd randomly selected from the database. Those were the days. Speaking of old old versions... Guess who *finally* got his computer equipment back from the EffBeeEye? Yuppers... Nearly 5 years later and I'm now the proud re-owner of some vintage 1998 equipment. Well, the DLT 35/70 drive is still useful... Glad I got that back. Fired up my main machine (after re-hooking up just about EVERY cable inside and removing the Evidence tape all over everything)... And there it was, my Prime95 16.(4?) running. Too bad the exponent has LOOONG since been first/second time checked... In the 5M range. Hey, it was a pretty new first-time check at the time. :) I was tempted to pull a Mitnick and try to auction off my loose hard drives, each bagged and tagged Evidence, FBI - Washington DC, but I'm just too curious to see what exactly I had on those drives... Been so long, I've forgotten. Plus I'm not really thinking people would pay for crap like that. :-D Maybe I should at least take pictures to remember the moment... Each hard drive, even each floppy and tape they took, each CD etc. has a hand-written serial # sticker affixed to it now. They are organized, even if they didn't know how to hook everything back up inside the computer (fans hanging loose, SCSI drives plugged into the wrong ports, etc). -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John R Pierce Sent: Tuesday, August 19, 2003 8:41 PM To: Mersenne discussion list Subject: Re: Mersenne: Howdy Just joined the list and wanted to say hey. I am new to the project and find it very interesting. Does anyone know how long it has been running? since at least 1995. my bad, apparently the original prime95 came out in january 1996 this per the FAQ's and stuff on the mersenne.org site. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 20 Aug 2003 00:53:42 -0400 From: Rick Pali [EMAIL PROTECTED] Subject: RE: Mersenne: Howdy Yeah, I was also trying to remember how long it's been around... I guess I really did catch it near the start. I still have those fond memories of emailing George with the exponents I'd randomly selected from the database. Those were the days. Too true...I got in about a year after it started if memory serves. I remember when PrimeNet came on line...I got as high as #15 before I started my descent into the triple digits. :-) Rick. - -+--- [EMAIL PROTECTED] http://www.alienshore.com/seeking/ _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 20 Aug 2003 06:45:16 +0100 From: Daran [EMAIL PROTECTED] Subject: Re: Mersenne: Howdy On Tue, Aug 19, 2003 at 09:25:30PM -0700, Aaron wrote: Guess who *finally* got his computer equipment back from the EffBeeEye? Yuppers... Nearly 5 years later and I'm now the proud re-owner of some vintage 1998 equipment. Well, the DLT 35/70 drive is still useful... Glad I got that back
Mersenne Digest V1 #1081
Mersenne Digest Friday, July 11 2003 Volume 01 : Number 1081 -- Date: Wed, 09 Jul 2003 10:03:56 +0300 From: Oleg V.Cat [EMAIL PROTECTED] Subject: Re: Mersenne: PrimeNet server unavailable? Hello Robin Stevens [EMAIL PROTECTED]! ___ In [EMAIL PROTECTED], on 07/09/03 at 09:58 AM, Robin Stevens [EMAIL PROTECTED] said: - - - - - - - - - - - - - - - - - - - - - - Anyone else having trouble reaching the PrimeNet server? Several of my clients have been unable to check in for several days, although some did manage last night. At the moment it looks as though the clients are attempting TCP port 80 connections to 66.45.51.160 (no rDNS), which fail. Hmm... MB this is an answer: What does PrimeNet error 12002 mean? The message forwarding process at Entropia is down. Version 21 clients and earlier sends messages to entropia.com which are then forwarded to mersenne.org. Version 22 clients and later send messages directly to mersenne.org. The best solution is to get version 22 or later. Alternatively, you can wait for Entropia's message forwarding process to be restarted which can take several days. (I personally also get error No.1, not 12002, but I have some clients without possibility to change them from v18 :-( ) - -- \Cat /\ /\ Oleg V.Cat [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 9 Jul 2003 10:38:27 +0100 From: Robin Stevens [EMAIL PROTECTED] Subject: Re: Mersenne: PrimeNet server unavailable? On Wed, Jul 09, 2003 at 10:03:56AM +0300, Oleg V.Cat wrote: Hmm... MB this is an answer: What does PrimeNet error 12002 mean? The message forwarding process at Entropia is down. Version 21 clients and earlier sends messages to entropia.com which are then forwarded to mersenne.org. Version 22 clients and later send messages directly to mersenne.org. The best solution is to get version 22 or later. Alternatively, you can wait for Entropia's message forwarding process to be restarted which can take several days. Thanks - that looks useful. I'd looked at the entry for 2250 errors (which are what the clients report) but not seen that one. I suspect when I look around I'll find that the clients which are failing to report are all running v21. Mass upgrade time! Robin - -- - --- Robin Stevens [EMAIL PROTECTED] - Oxford University Computing Services --- Web: http://www.cynic.org.uk/ - --- (+44)(0)1865: 273212 (work) 273275 (fax) Mobile: 07776 235326 --- _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 11 Jul 2003 15:32:27 -0700 From: Robert Braunwart [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #1080 Hi Everybody, I'm having trouble with one of my computer contacting PrimeNet. It is supposed to connect every day, but hasn't connected for two weeks. I get the Error 29 message. I have looked at the explanation for Error 29 at PrimeNet, but none of the four possibilities apply to me. I am running Prime95 v. 21.4 and have not upgraded in a long time. Also, I have been running Prime95 on this computer for a long time. Any suggestions? - --Bob Braunwart _ STOP MORE SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1081 ***
Mersenne Digest V1 #1079
Mersenne DigestThursday, July 3 2003Volume 01 : Number 1079 -- Date: Tue, 1 Jul 2003 12:47:22 -0800 (AKDT) From: Gordon Bower [EMAIL PROTECTED] Subject: Mersenne: Error 12002 I've seen sporadic episodes of error messages before during temporary server outages. However, haven't seen one that lasted this long. I now have several machines that have been unable to report for six days in a row. One of them is nearly out of work (though I can reserve assignements manually if I need to.) Looking through the Forum archives it appears Error 12002 is a version 21-specific problem that occurs when entropia.com is down even if mersenne.org is up. On Saturday entropia.com was indeed down. However, entropia's website has been up since sometime Sunday, and I have *still* been getting hourly 12002s on three different systems. No firewalls on my end, and no settings have changed on my end either. Any advice? I would also ask the keeper of the faq to add a few new lines to it about these new (since 2 years or so ago) error messages that aren't described in the online information. GRB _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 03 Jul 2003 16:43:18 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: version 23.5 Version 23.5 is available. See http://www.mersenneforum.org/viewtopic.php?t=3 for downloading links. This is a beta release, but should work OK. Speed improvements of 3 to 8% can be expected for Athlon, Duron, Pentium 3, and Celeron 2 owners. Four or five changes have been added to reduce the chance of another false prime report. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 04 Jul 2003 00:46:39 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Re: Mersenne: Error 12002 At 12:47 PM 7/1/2003 -0800, Gordon Bower wrote: Looking through the Forum archives it appears Error 12002 is a version 21-specific problem that occurs when entropia.com is down even if mersenne.org is up. On Saturday entropia.com was indeed down. However, entropia's website has been up since sometime Sunday, and I have *still* been getting hourly 12002s on three different systems. I would also ask the keeper of the faq to add a few new lines to it about these new (since 2 years or so ago) error messages that aren't described in the online information. As suggested, I've added error 12002 to the FAQ. I've also emailed Scott to see if he can get Entropia to restart GIMPS message forwarding process _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1079 ***
Mersenne Digest V1 #1078
Mersenne Digest Tuesday, July 1 2003 Volume 01 : Number 1078 -- Date: Sat, 28 Jun 2003 22:23:41 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Double Checking On Saturday 28 June 2003 18:47, you wrote: Will the 64-bit residue be the SAME when a given exponent was originally Lucas-Lehmer tested with a 384K FFT, but the double-check is performed using a 448K FFT ? Hopefully - in fact the whole 2^p-1 bit residue R(p) should be the same! R(2)=4 R(n+1) = R(n)^2 -2 modulo 2^p-1 I don't see how the FFT run length should affect this ... in fact the FFT is only used at all because it's the most efficient method known of doing the multiplication of very large numbers. If the residues calculated with 384K FFT 448K FFT are different, then: - - most likely, at least one of the runs has been affected by a glitch of some sort; - - or, the 384K FFT run length is too small some data value was rounded to the wrong integer during the run - I do not think that this is very likely unless serious abuse has been made of the SoftCrossoverAdjust parameter; - - or, there is a systematic error in the program code for at least one of the run lengths. Since short runs (400 or 1000 iterations) have been crosschecked with various FFT run lengths, again I do not think this is very likely. Regards Brian Beesley _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 28 Jun 2003 22:23:41 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Double Checking On Saturday 28 June 2003 18:47, you wrote: Will the 64-bit residue be the SAME when a given exponent was originally Lucas-Lehmer tested with a 384K FFT, but the double-check is performed using a 448K FFT ? Hopefully - in fact the whole 2^p-1 bit residue R(p) should be the same! R(2)=4 R(n+1) = R(n)^2 -2 modulo 2^p-1 I don't see how the FFT run length should affect this ... in fact the FFT is only used at all because it's the most efficient method known of doing the multiplication of very large numbers. If the residues calculated with 384K FFT 448K FFT are different, then: - - most likely, at least one of the runs has been affected by a glitch of some sort; - - or, the 384K FFT run length is too small some data value was rounded to the wrong integer during the run - I do not think that this is very likely unless serious abuse has been made of the SoftCrossoverAdjust parameter; - - or, there is a systematic error in the program code for at least one of the run lengths. Since short runs (400 or 1000 iterations) have been crosschecked with various FFT run lengths, again I do not think this is very likely. Regards Brian Beesley _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 29 Jun 2003 01:42:26 -0400 From: Pierre Abbat [EMAIL PROTECTED] Subject: Mersenne: Squaring huge numbers I am investigating 64-100 sequences, which are chains of bases such that the number written 100 in each is written 64 in the next (e.g. 8,10,16,42). I quickly wrote a Python program to compute them. It is now computing the square of a 1555000 digit number and has been doing so since the 17th. What squaring algorithm is Python using? Is there a faster way of squaring numbers where the number of digits doubles at each iteration? phma - -- .i toljundi do .ibabo mi'afra tu'a do .ibabo damba do .ibabo do jinga .icu'u la ma'atman. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 29 Jun 2003 07:24:26 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Squaring huge numbers On Sunday 29 June 2003 05:42, Pierre Abbat wrote: I am investigating 64-100 sequences, which are chains of bases such that the number written 100 in each is written 64 in the next (e.g. 8,10,16,42). I quickly wrote a Python program to compute them. It is now computing the square of a 1555000 digit number and has been doing so since the 17th. What squaring algorithm is Python using? I don't know offhand, but: (a) Python is interpreted; (b) the Python interpreter is open source, so it shouldn't be hard to find out how it does big integer arithmetic; (c
Mersenne Digest V1 #1077
Mersenne DigestSaturday, June 28 2003Volume 01 : Number 1077 -- Date: Sun, 22 Jun 2003 20:31:04 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: M997 factored Bruce Dodson has found an incredible 57 digit factor of M997 using prime95's ECM. This is two digits longer than the previous longest factor found using the ECM method. Here's the output from prime95: ECM found a factor in curve #14, stage #2 Sigma=6329517009540700, B1=4400, B2=429000. UID: bd1024tmp, M997 has a factor: 167560816514084819488737767976263150405095191554732902607 Cofactor is a probable prime! Congratulations to Bruce on this improbable discovery! _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 28 Jun 2003 13:47:33 -0500 From: [EMAIL PROTECTED] (Mikus Grinbergs) Subject: Mersenne: Double Checking Will the 64-bit residue be the SAME when a given exponent was originally Lucas-Lehmer tested with a 384K FFT, but the double-check is performed using a 448K FFT ? mikus _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1077 ***
Mersenne Digest V1 #1074
Mersenne DigestSaturday, June 14 2003Volume 01 : Number 1074 -- Date: Wed, 11 Jun 2003 22:58:49 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: Re: M#40 verification run More bad news to report. I've just gotten a hold of the results.txt file from the original run. There were five SUM(INPUTS) != SUM(OUTPUTS) error during the run. Historically, five errors during a run means there is less than a 50% chance the final LL result will be correct. Now I have to try and figure out what safety checks can be added to prevent false alarms. So far, I have 2 changes planned: 1) Prime95 does not tell the server how many errors occurred for an LL test with a prime result. I'll fix this. Knowing their were 5 errors would have raised red flags earlier on. 2) I'll change prime95 to NOT delete the save files when a new prime is found. When a prime is reported, I'll ask for the save file and rerun the last 30 minutes of the test. I think this would have helped in this case. This measure also deters a hacker. It might be easy for a hacker to spoof a prime report - but he'll have difficulty generating a save file that reports the number as prime after the final 30 minutes of LL testing. There is still a chance this really is prime, we'll know on Friday. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 12 Jun 2003 05:55:31 -0400 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: M#40 verification run - --On Wednesday, June 11, 2003 3:15 PM -0400 George Woltman [EMAIL PROTECTED] wrote: Possibilities are: 1) The original run was flawed or there is a bug in the version of prime95 used. It is hard to imagine a bug or hardware glitch that generates an all zero LL result. If memory is zeroed at some point, the next LL iterations are -2, 2, 2, 2, ... 2) My overclocked machine generated an undetected error or the prime95 version I'm using has a bug that is affecting my result. 3) I was debugging an out-of-memory bug report last night. It is theoretically possible there is an OS bug that affects other processes in these severe circumstances. 4) Someone hacked the server. Is this a concern? Nathan _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 12 Jun 2003 06:07:36 -0400 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: Re: M#40 verification run - --On Wednesday, June 11, 2003 10:58 PM -0400 George Woltman [EMAIL PROTECTED] wrote: 2) I'll change prime95 to NOT delete the save files when a new prime is found. When a prime is reported, I'll ask for the save file and rerun the last 30 minutes of the test. I think this would have helped in this case. This measure also deters a hacker. It might be easy for a hacker to spoof a prime report - but he'll have difficulty generating a save file that reports the number as prime after the final 30 minutes of LL testing. That is a collosal understatement. Every modulo operation destroys information, and I'm not sure whether one COULD construct such a file. Nathan _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 12 Jun 2003 17:58:56 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Re: M#40 verification run On Thursday 12 June 2003 10:07, Nathan Russell wrote: That is a collosal understatement. Every modulo operation destroys information, and I'm not sure whether one COULD construct such a file. Indeed. In general there will be more than one x such that x^2-2 = R modulo 2^p-1 so, working backwards through a number of steps, you would have only a very small probability of deriving the same starting condition. Even if the equation was easy to solve in reverse... Regards Brian Beesley _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 12 Jun 2003 17:58:56 + From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Re: M#40 verification run On Thursday 12 June 2003 10:07, Nathan Russell wrote: That is a collosal understatement. Every modulo operation destroys information, and I'm not sure whether one COULD construct such a file. Indeed. In general there will be more than one
Mersenne Digest V1 #1073
Mersenne Digest Wednesday, June 11 2003 Volume 01 : Number 1073 -- Date: Tue, 03 Jun 2003 10:25:03 -0700 From: Phil Moore [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne archives Does anyone know what happened to the archives? http://www.mail-archive.com/[EMAIL PROTECTED]/ _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 3 Jun 2003 10:55:18 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne archives Does anyone know what happened to the archives? http://www.mail-archive.com/[EMAIL PROTECTED]/ well, http://www.mail-archive.com says... June 2, 2003 Mail-Archive is experiencing technical problems, all archives are temporarily offline and are being actively restored from backup. Because of the very large volume of data, this process takes a long time - multiple days so far, and possible a few more are required. Thank you for your patience. Estimated time of completion June 4 20:00 PST Jeff Breidenbach [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 03 Jun 2003 21:29:24 +0200 From: Jean Penné [EMAIL PROTECTED] Subject: Re: Mersenne: 40th Mersenne Prime Found (probably)! I am very happy to learn about this new success of GIMPS !! Congratulations to all ! Jean. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 11 Jun 2003 15:15:12 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: M#40 verification run I've tried to keep everyone promptly informed of Mersenne news - good or bad. So, here we go... My verification run of M#40 just completednot prime. Now we wait for Guillermo Ballester Valor's run to complete in the next few days. Our runs matched at 13 million iterations. Possibilities are: 1) The original run was flawed or there is a bug in the version of prime95 used. It is hard to imagine a bug or hardware glitch that generates an all zero LL result. If memory is zeroed at some point, the next LL iterations are -2, 2, 2, 2, ... 2) My overclocked machine generated an undetected error or the prime95 version I'm using has a bug that is affecting my result. 3) I was debugging an out-of-memory bug report last night. It is theoretically possible there is an OS bug that affects other processes in these severe circumstances. I have save files every million iterations. If this really is a new Mersenne prime, then I'll rerun the last iterations again to make sure the latest prime95 does not have a bug. _ Unsubscribe list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #1073 ***
Mersenne Digest V1 #866
Mersenne Digest Monday, July 2 2001 Volume 01 : Number 866 -- Date: Sun, 1 Jul 2001 01:07:02 +0200 From: Hoogendoorn, Sander [EMAIL PROTECTED] Subject: RE: Mersenne: 33mio exponents Guido Lorenzini wrote: 1st observation: the beerman's computer named SKA4 seems to work simultaneously on 4 33mio exponents, since each exponent is getting iterations: how it come? If any Cpu is best working on just one copy of prime95, even a dual cpu PC should have 2 computer ID...You may see the same situation with DEJEFLATERIC of netconx, but, once again, these are just examples. It is possible to use the same computer ID for several computers. This can happen if you copy the prime95 directory to other computers. For example when installing prime95 over a network, or when cloning a disk to another pc. 2nd: Sometimes it happens that an exp. is assigned to an unspecified computer ID (for example, the account kpgcfd, has some). Is it possible? Yes, you can leave the computer ID blank. If you leave your account ID blank the primenet server asigns you one. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 1 Jul 2001 09:05:12 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: 33mio exponents On 30 Jun 2001, at 20:16, Guido Lorenzini wrote: 1st observation: the beerman's computer named SKA4 seems to work simultaneously on 4 33mio exponents, since each exponent is getting iterations: how it come? If any Cpu is best working on just one copy of prime95, even a dual cpu PC should have 2 computer ID...You may see the same situation with DEJEFLATERIC of netconx, but, once again, these are just examples. This looks odd, but in fact I can set up as many systems as I like with the same computer id, making many systems appear to be one. I can also confuse the issue by changing the computer id on a single system, making one system appear to be many. 2nd: Sometimes it happens that an exp. is assigned to an unspecified computer ID (for example, the account kpgcfd, has some). Is it possible? Yes. When I joined the project more than three years ago, blank computer IDs were very common. The server software has been changed to automatically assign computer IDs to new systems being set up when the user has not set the computer ID himself, but there are still a number of systems running with blank IDs which have been active since before this change was made. 3rd: Net_Force seems to have some wonderful machines, called (properly!)10MIL-X: they are able to test (or factoring) dozen of 33mio exponents in 2 months time or more! Any information about the processor of these machines? Or is it relevant the fact bits? (60 or I don't know what's going on here. The fact bits just means that when the assignment was given out, that's the factoring depth that was done. For exponents of this size, you're supposed to complete factoring to 68 bits before starting the LL test. 4th: netconx reserved 2,325 33mio exps on its computer ID DEJECHRISTIA, most of them with 60 fact bits or less. It started getting 'em on June 20th at 4:59 AM, one each two minutes, till June 23th at 12:07 PM. Now it may be too long to explain but this mass of 33mio exps. seems to be bounced like a ball from an account to another (e.g. from kpgcfd, ID mac_233, on May to netconcx by now); then these exponents, assigned in June to netconx to computer ID DEJECHRISTIA, were assigned to the same account netconx, but to a machine called BART, in April 7th. I really do not understand what's going on... Is there anybody who may give me do not understand what's going on... Me neither. I reckon that big block of exponents expired got picked up again. The only thing that seems to make any sense is that someone is running in a Beowulf cluster that happens to have no net connection (maybe because it's running in a highly secure environment), so they're using one system to collect work then farm it out locally. Anyway it's doing no harm, so long as they leave a few assignments for other people to pick up! It will be interesting to see what happens in a few months, when (if my guess is true) there may be a big block of results coming in more or less at the same time. Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 3 Jul 2001 09:20:22 +0200 From: Lars Lindley [EMAIL PROTECTED] Subject: Mersenne: Solaris 8 This is a multi-part message in MIME format. - --=_NextPart_000_0032_01C103A1.628CB0D0 Content-Type
Mersenne Digest V1 #865
Mersenne DigestSaturday, June 30 2001Volume 01 : Number 865 -- Date: Tue, 26 Jun 2001 09:47:52 +0100 From: Andy Hedges [EMAIL PROTECTED] Subject: RE: Mersenne: Proth observations Anyone have any idea why for k = 659 there are very little primes? In fact for k up to 20 there are none (I haven't found any in this range yet!). Andy - -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] Sent: 23 June 2001 02:17 To: Gordon Bower; [EMAIL PROTECTED] Subject: Re: Mersenne: Proth observations Gordon Bower [EMAIL PROTECTED] observes After seeing a post on this list a few weeks ago I decided to branch out and try a few ranges from Michael Hartley's page looking for k*2^n-1 primes. I must say there is a bit of a thrill in actually discovering a new prime every day I run the program instead of proving two numbers a month composite. :) I assumed that one value of k was pretty much the same as any other as far as execution time and the chance of finding primes. To my surprise this turned out not to be so: On the P3-500, for most 650k750, it takes about 5 hours for 16000n32000 and 12 hours for 32000n48000 -- but for k=701 it took less than 2 and just over 6 hours, respectively. The phenomenon is reproducible, doesn't seem to be an artifact of other programs or reboots or suchlike. Any number theorists care to explain what is special about k=701 that makes it easy to check for primality? Fix k = 701. We check that If n == 1 (mod 2) then k*2^n == 1 (mod 3) If n == 0 (mod 4) then k*2^n == 1 (mod 5) If n == 6 (mod 8) then k*2^n == 1 (mod 17) If n == 0 (mod 3) then k*2^n == 1 (mod 7) Therefore k*2^n - 1 can be prime only if n == 2 or 10 (mod 24). We can eliminate more potential values of n using If n == 8 (mod 18) then k*2^n == 1 (mod 19) If n == 18 (mod 20) then k*2^n == 1 (mod 41) If n == 6 (mod 28) then k*2^n == 1 (mod 29) Some congruences are redundant; for example If n == 6 (mod 12) then k*2^n == 1 (mod 13) eliminates nothing new. k = 701 has less such redundancy than the typical k. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 26 Jun 2001 10:09:23 +0100 From: Andy Hedges [EMAIL PROTECTED] Subject: RE: Mersenne: Proth observations Are all primes of this form probable primes of this form? Andy - -Original Message- From: Hoogendoorn, Sander [mailto:[EMAIL PROTECTED]] Sent: 23 June 2001 10:02 To: '[EMAIL PROTECTED]' Subject: RE: Mersenne: Proth observations Brian J. Beesley Wrote: My strategy is: (1) run Proth at medium priority in factoring only mode to eliminate candidates with small factors; For step 1 i use Newpgen. I think this is better configurable then proth in how far or long you want to factor. Don't know which is the fastest of the two. (2) on the same system, run PRP at low priority to check the survivors from stage 1 for probable primes; (3) on a different system (normally running Prime95), run Proth at medium priority to verify the probable primes. (If you don't have a spare system it would be best to do this in a seperate directory so as to save keep changing the Proth setup!) BTW so far _every_ probable prime I've found using PRP has been accepted as a genuine prime by Proth, though this is certainly not guaranteed. Same here If you break the run down as above you will see that some values of k yield a much smaller proportion of candidates for psuedo-prime testing than others. Or, to put it another way, some values of k give a much higher percentage of k.2^p-1 with small factors than others. For some k's you have to test more the twice as many candidates in the same range of n's Sander _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 26 Jun 2001 19:14:06 +0200 From: =?iso-8859-1?Q?Torbj=F6rn_Alm?= [EMAIL PROTECTED] Subject: Re: Mersenne: Proth observations Hi! It is a general observation, that while some values for k give a good harvest of new primes, others give very little. This is obvious if you look at the tables of primes
Mersenne Digest V1 #864
Mersenne Digest Monday, June 25 2001 Volume 01 : Number 864 -- Date: Fri, 22 Jun 2001 02:08:31 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: Good news for Pentium 3 and Celeron 2 owners I feel it is ridiculous that George has to beg/borrow the latest architecture in order to optimise Prime95. I also know from being a member of the prime search community for the last three years the amount of hard work George puts into the project. agreed. how come AMD isn't burying George in processors so he can better optimize for their architecture? _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 22 Jun 2001 06:23:14 -0400 (EDT) From: Kel Utendorf [EMAIL PROTECTED] Subject: Re: Mersenne: Good news for Pentium 3 and Celeron 2 owners On Fri, 22 Jun 2001, John R Pierce wrote: I feel it is ridiculous that George has to beg/borrow the latest architecture in order to optimise Prime95. I also know from being a member of the prime search community for the last three years the amount of hard work George puts into the project. agreed. how come AMD isn't burying George in processors so he can better optimize for their architecture? Sounds like a good idea to me. I've long been impressed by the amount of work that George puts into this project, and would be very willing to contribute a few bucks so that we could purchase the needed hardware to further the project. The members of Team Anandtech have often contributed money and/or hardware to various things. I believe they supplied the $$$ and hardware for the team's personal proxy server for their distributed.net efforts, and have contributed to at least one game box for the team members. Why can't we do something similar? Of course, George would have to find the time to do all of this wonderful new coding...;-) Kel _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 22 Jun 2001 13:12:41 US/Eastern From: [EMAIL PROTECTED] Subject: Mersenne: Factoring on a P4 For some reason, I am at a loss to explain, a v21 P4 1.4 GHz factors significantely slower that a P3 v20 700MHz. Is there a reason, and solution, for this? Bradford J. Brown - - This message was sent using GSWeb Mail Services. http://www.gasou.edu/gsumail _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 22 Jun 2001 18:46:43 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Factoring on a P4 On 22 Jun 2001, at 13:12, [EMAIL PROTECTED] wrote: For some reason, I am at a loss to explain, a v21 P4 1.4 GHz factors significantely slower that a P3 v20 700MHz. Is there a reason, and solution, for this? Good question. AFAIK George has done nothing to the factoring code. You will see a big speed loss if you compare factoring under 2^64 with factoring over 2^64 on _any_ system - that's simply explained by triple- precision integer arithmetic being much slower than double-precision integer arithmetic. Intel's development for the P4 was very much geared towards making SSE2 work well. Unfortunately this left less room in the silicon for some of the ordinary integer stuff on which the factoring code (but not the LL testing code) in Prime95 depends. If memory serves me right, the 32 bit by 32 bit integer multiply instruction was badly hit by this. Consequently the factoring throughput of a P4 would be expected to be considerably less than that of a PIII running at the same clock speed. I would expect that a PIII-700 and a P4-1400 would probably run factoring at about the same speed. For now, those who are lucky enough to have P4 systems are probably best advised to stick to LL testing (and trial factoring - which will not be affected by any inefficiency in the P4 integer instructions), leaving trial factoring to those with slower systems. Conversely, if you need a system with optimal integer performance, you'd be much better advised to buy a system based on a fast Athlon processor than a system based on a Pentium 4. Athlons running integer code even run much cooler; the FPU turns itself off when it isn't needed, leading to a big drop in current consumption. BTW there was an unreasonable acceleration of trial factoring between the P5 architecture (Pentium Classic/MMX) and the P6 architecture (Pentium Pro / PII / PIII
Mersenne Digest V1 #863
Mersenne Digest Friday, June 22 2001 Volume 01 : Number 863 -- Date: Wed, 20 Jun 2001 08:06:28 +0200 From: george de fockert [EMAIL PROTECTED] Subject: Re: Mersenne: Prime95 - V21.1.1 aka v21a - - Original Message - From: Brian J. Beesley [EMAIL PROTECTED] It would also be interesting to find out if the PIII prefetch code benefits the AMD K6 processor. The K6-2 and K6-3 do have an Athlon- compatible prefetch instruction, though it's using 32-byte cache lines and there is no prefetch queue i.e. only one prefetch can be active at any time. Just tried it on my k6-2, needs CpuSupportsPrefetch=1 in local.ini, and results in an illegal instruction exception. So the program probably does not use the AMD 3dnow! prefetch instruction, PREFETCH(W), but one of the intel MMX2 or SIMD prefetch instructions not on the K6-2, PREFETCHNTA orPREFETCHT[123] BTW what happens to the prefetch instructions for those processors (like PII) that don't support prefetch? See above for the K6-2 George de Fockert _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 20 Jun 2001 08:51:11 -0700 From: Eric Hahn [EMAIL PROTECTED] Subject: Re: Mersenne: Prime95 - V21.1.1 aka v21a George Woltman wrote: Some Athlons are seeing a speed increase others are not. The two that I know are not enjoying a speed increase are running under Win2K. Maybe there is a bug in the way v21.1 determines if prefetch is supported. For those Athlon owners that are not seeing a speed boost, try setting CpuSupportsPrefetch=1 in local.ini This is a possibility. The other possibility is that there might be something in Windows that is interfering. The reason I say this, is that I have a P3 running at 733Mhz, and after a reboot, Prime95 was back to running at the same iteration time before v21 starting running. After stopping Prime95 and adding the line to local.ini, it was back to the increased speed. Interesting... to say the least... Eric P.S. BTW, this P3 is running Win98SE... _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 20 Jun 2001 16:55:04 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: More v21 Hi all, Regarding some of the comments on v21: The strange data output when doing an Advanced/Time on 10,000,000 is due to some instrumentation I accidentally left in. I have removed it and maybe it will speed up the program by a very, very, very tiny amount. You can download it at ftp://mersenne.org/gimps/p95v21a.zip I've built a Windows NT Service version and a Linux version. You can download them at ftp://mersenne.org/gimps/p95v21n.zip and ftp://mersenne.org/gimps/p95v21x.zip respectively. They have been through the robust QA process of proving M11213 prime. Use at your own risk! Brian Beesley, a big QA volunteer, will undoubtedly download the Linux version and report bugs or a higher level of confidence in mprime's capabilities. Since the prefetch code seems to work on the Athlon, I won't be needing the services of Athlon programmers or Orlando residents just now. Thanks to those that offered. Although, I'm sure we could get a few more percent by using PREFETCHW or by a modified memory layout for the 64-byte cache lines, I'll wait until v21 is finalized before looking at any more changes. Finally, the PPro, PII, and Celeron 1 do not crash when a prefetch instruction is encountered. This indicates to me that Intel planned on putting this instruction in prior to the PIII but ran into technical difficulties or time constraints. These CPUs are affected only by the prefetch instructions using up some cache space and decoder bandwidth. Thus, I'm reluctant to increase prime95's size by a third to support 4 different FFT algorithms: Pentium classic, Pentium Pro, Pentium Pro with prefetching, and SSE2. I haven't made a final decision yet (although I sure wish I'd put the FFT code in a DLL!) Regards, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 20 Jun 2001 15:32:24 -0700 (PDT) From: Francois Gouget [EMAIL PROTECTED] Subject: Re: Mersenne: Prime95 - V21.1.1 aka v21a On Tue, 19 Jun 2001, Brian J. Beesley wrote: [...] Unfortunately I can't contribute timings to this argument as none of my three Athlon systems can run Prime95 (they're all linux systems
Mersenne Digest V1 #862
Mersenne Digest Tuesday, June 19 2001 Volume 01 : Number 862 -- Date: Sun, 17 Jun 2001 16:20:03 -0400 (EDT) From: Jason Stratos Papadopoulos [EMAIL PROTECTED] Subject: Mersenne: finding large primes for integer FFTs (long) Hey everybody. I've realized after finishing an integer convolution library for the Alpha (using number-theoretic FFTs) that even a nice 64-bit processor like the Alpha couldn't give me the speed I wanted for integer-only Mersenne-mod squaring. I've also wanted for a while to build integer-only convolution on x86 machines that was at least somewhat comparable to Prime95 in speed. The big problem with the code now is that integer multiplies still take too long. A floating point FFT can not only rearrange its structure to minimize the amount of arithmetic but can also take advantage of floating point hardware that can finish a result (or even two) every clock cycle. In contrast, 62-bit integer modular multiplication takes a minimum of 6 clocks on an Alpha ev6 (using highly vectorized assembly code) and with extreme contortions takes 40 clocks on a Pentium and 30 clocks on an Athlon. There are also no simplifications you can make to a number-theoretic FFT, because typically a 4th- or 8th- root of unity has no special form that reduces the amount of arithmetic when you're working modulo a 62-bit prime (I use 62 bits because carries are easier to handle than with 64-bit primes). Choosing different kinds of primes won't help either. There are maybe 8 primes of 32-bit size that could be used for a large integer FFT, but none of them allow a large root of 2 like a Mersenne-mod DWT requires (never mind that you'd need two of them and CRT reconstruction). For primes of the form i*2^32 + 1, with i between 2^30 and 2^31, there are 14 primes that allow a large root of 2 and hence allow a big DWT; however, I can't find any primitive roots for these primes that allow simple roots of unity, and so FFT speed is limited to the cycle counts mentioned previously. As several people on this list are aware, 2^64-2^32+1 is prime, allows for a big DWT, and has primitive roots that allow for simple 64th roots of unity. I've written a lot of x86 assembly code for small FFTs in a finite field modulo this prime, and it seems that an FFT butterfly takes 20-25 clocks on a Pentium (probably somewhat fewer on an Athlon). While this is wonderful compared to general 64-bit arithmetic, it's a far cry from the 10 clocks or so that a floating-point FFT butterfly may need. Dealing with carries and borrows out of 64 bits also slows it down on the Alpha, to the point where (on paper, at least) it's just as fast to use one of those 14 other primes that do the same job. Nussbaumer convolution and Schonhage-Strassen squaring are other candidates, and have very little arithmetic (Nussbaumer in particular can be optimized to be really fast), but their memory efficiency is horrible. Both require arithmetic on huge numbers in their initial stages, and there's no way to load a block of data into cache and spin on it for several FFT passes like you can do with a floating point FFT. There's also much more movement of data with these algorithms, although with Nussbaumer you can minimize that by making the movement virtual. Prime95 gets most of its speed from very careful data placement that minimizes memory traffic, and these algorithms are not good substitutes. Finally, there are fast Galois transforms that use complex arithmetic but with integers. A large-radix FFT is possible here, and using Mersenne primes makes that arithmetic easier; but each complex multiply has four of those awful integer multiplies in it, and even with a split-radix formulation the work only seems to be about 10%-15% less than a conventional integer FFT, for much more complexity. That's on the Alpha, which can handle complex integer multiplies enormously faster than x86 machines can. Performance comparable to that of prime95 would require at least a factor of two better than that. I first discovered GIMPS around the middle of 1996, and I guess I'm spouting off like this because years of sweating on all these methods with no breakthrough has made me bitter. I want to contribute more than just one dinky computer to this project, because computational number theory and code optimization both fascinate me. There may be a way. Nobody seems to have considered using very large primes for an integer FFT (by large I mean 512 bits or more). Using huge primes like this means less memory consumption (the runlengths are smaller), more flexible FFT sizes (since the number of bits you pack into an array element can vary over a wide range, you can use power-of-2 run- lengths and still get the effect of a non-power-of-2 size FFT), and the cost of arithmetic is amortized over many machine words. As with small primes, the chief obstacle is to find a way to do relatively big
Mersenne Digest V1 #861
Mersenne Digest Sunday, June 17 2001 Volume 01 : Number 861 -- Date: Tue, 12 Jun 2001 20:48:12 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Re: Mersenne: Interesting Results.txt Entries Hi, At 05:10 PM 6/11/2001 -0500, C. Daniel Sheets wrote: then had 3 more SUMOUT errors, then came these interesting lines: P-1 found a factor in stage #2, B1=15, B2=1912500. ERROR: Factor doesn't divide N! Could someone please tell me what these are saying. The P-1 factoring code thought it found a factor of the Mersenne number. The program then verifies the factor and unfortunately found that the factor did not really divide the Mersenne number. Obviously, you've either found a bug in the code or you've got a hardware glitch or interference from other software. I have since added/reassigned the exponent to another of my computers to see if the same thing happens. Good idea. I am suspect of the computer because of the SUMOUT errors and will look at heat and memory issues. Normally, ILLEGAL SUMOUTS are caused by device drivers not properly saving the FPU state. If you start getting other types of errors, then you have a real hardware problem. Regards, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 13 Jun 2001 12:01:15 -0700 From: Michael Gebis [EMAIL PROTECTED] Subject: Re: Mersenne: Interesting Results.txt Entries I am suspect of the computer because of the SUMOUT errors and will look at heat and memory issues. Thanks for your time. I saw that George already explained the most likely causes of these errors. However, since you brought up memory issues, I'd like to point out memtest86: http://www.memtest86.com/ Whenever I build a new system, I stress test it by running two programs: memtest86 to verify the memory, and prime95 to verify most everything else. Mike _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 17 Jun 2001 19:50:05 +0200 From: =?Windows-1252?Q?Ignacio_Larrosa_Ca=F1estro?= [EMAIL PROTECTED] Subject: Mersenne: Top Producers Hi, I sent during the last week 10/16 of June five results, as incicate my personal account report: 10763341 64 0xACC8572A17E3CE__11-Jun-01 07:16 P3-450AIRD05 10878943 64 0xBEE3F9DCA8E59B__11-Jun-01 07:16 P3-600RDIEST 11178493 64 0x43EFB69984C69E__15-Jun-01 08:12 PII300-RDIE3 11812687 64 0x870A38C67BE85F__12-Jun-01 07:18 P3-667AIRD10 12189953 64 0x618103991F8D30__13-Jun-01 07:55 P3-667AIRD11 But, in the Top Producers List (http://www.mersenne.org/top.htm), the number of exponents tested increase only from 811 to 815. Where is the exponent lost? Best regards, Ignacio Larrosa Cañestro A Coruña (España) [EMAIL PROTECTED] ICQ #94732648 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #861 **
Mersenne Digest V1 #860
Mersenne Digest Monday, June 11 2001 Volume 01 : Number 860 -- Date: Fri, 8 Jun 2001 12:06:58 -0700 From: Pardoe, Richard (PRDR) [EMAIL PROTECTED] Subject: RE: Mersenne: Strange behaviour Guido: No problem with taking up my time. From the description of the problem (machine is unusable during Stage 2), it sounds like you may have given Prime95 too much memory. As a result, not enough memory is left for your other processes. There is a nice description of setting the available memory in the readme.txt.(about halfway into the document). What is your machine memory and how much of it have you allocated to Prime95 for factoring? (Memory is set under Options - CPU) Finally, yest it is normal that P95 runs a self-test for each of the different FFT sizes. Rich Pardoe - -Original Message- From: Guido Lorenzini [mailto:[EMAIL PROTECTED]] The Duron completed the stage 1 without any problem, but during the stage 2 the time per iteration has slow down a lot, from 0.650 sec/it to many minutes for just one iteration. Above all the pc is unusable, Is it better if I force prime95 to start p-1 factoring from zero once again, hoping any problem occurs this time? What may be the problem? Has anybody ever observed something like this? Last question: is it normal that prime95 runs a self test each time it is going to test with different FFT sizes? _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 8 Jun 2001 12:22:12 -0700 From: Aaron Blosser [EMAIL PROTECTED] Subject: Normal behaviour? - Re: Mersenne: Strange behaviour Guido, How much RAM is in your machine? Those large exponents can easily use a large chunk of memory when doing the P-1 testing, if I recall correctly. A relatively small amount of RAM could cause some serious paging to occur if it's running low. And it's normal for it to do a new test for a new FFT size. Your local.ini file should have lines in there indicating which FFT sizes it's done a test on already. I'd recommend letting it run those tests so it can make sure the boundaries are working right on your machine. Aaron - - - -- Original Message -- - - Don't like to take up your time, but the behaviour of Prime95 on a 750@795 Duron, P-1 factoring on 33.3mio exponent (B1=35 and B2=4025000), is quite strange. The Duron completed the stage 1 without any problem, but during the stage 2 the time per iteration has slow down a lot, from 0.650 sec/it to many minutes for just one iteration. Above all the pc is unusable, so I've decided to edit manually worktodo.ini: fromTest=33306743,68,0 to Test=33306743,68,1 to force prime95 to skip the factoring stage when the process was done for about 30% (The intermediate file mX306743 sizes 8,132 KB). I've tried to put everything on another machine but with no results: the behaviour was the same. Skipping the P-1 factoring stage shouldn't invalidate the LL test, as George says in undoc.txt: You can force prime95 to skip the trial factoring step prior to running a Lucas-Lehmer test. In prime.ini add this line: SkipTrialFactoring=1 By the way: I've done it but apparently nothing has changed. If I've understood properly, adding this line is like to manually edit worktodo.ini. Isn't it? Is it better if I force prime95 to start p-1 factoring from zero once again, hoping any problem occurs this time? What may be the problem? Has anybody ever observed something like this? Last question: is it normal that prime95 runs a self test each time it is going to test with different FFT sizes? Thank you in advance for answering and best regards from Italy. Guido72 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 09 Jun 2001 00:42:53 -0400 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: SUMOUT errors Thanks to all who helped me with the SUMOUT issue. For a variety of reasons, I bit the bullet and bought a hardware, external modem. Since doing so, I haven't had any problems (in fact, I had no problems after posting my first message, so it may have been something transitory involving the power supply). I also opened up the machine this past weekend and cleaned out some dust, in addition to removing and reinserting the memory, which had become slightly loose at one end. I also fixed the plastic air-directing device over the CPU, which was a little loose and causing some annoying noises. I don't know which issues, if any, were the problem, but I ran the machine through a 24-hour test after cleaning out the case
Mersenne Digest V1 #858
Mersenne Digest Saturday, June 2 2001 Volume 01 : Number 858 -- Date: Thu, 31 May 2001 14:13:27 +0100 From: Thomas Womack [EMAIL PROTECTED] Subject: Mersenne: Various ways of changing horses in mid-stream I have a P4/1300 which doesn't have an Internet connection. So, to get work units to and from it, I copy the whole prime95 directory to my K6/333 laptop which *does* have an Internet connection, and then run prime95.exe to get it to talk to the server. The K6/333 is something like a factor 24 slower than the P4/1300, and is often turned off, so I don't run any prime95 computations on it at all. The problem is, the P4 code in prime95.exe obviously won't work on the laptop. So when I run on the laptop, it rewrites local.ini to indicate that it's a Pentium [though it _doesn't_ change the MHz figure], and then collects work units as if it were a Pentium/1300. All I can think of is telling the K6/333 that it's actually a K6/8000, waiting for it to contact the server and collect work sized for a K6/8000, which the P4 should be able to run through at the correct rate, and then copying the worktodo.ini file obtained by this subterfuge to the P4 to get the work done. This seems somehow inelegant, particularly in that my account report now says that I have an 8000MHz K6 machine called Tom_s_P4 ... what's the right way of doing it? As another point, I have five Athlon/850 machines in the computer lab at college; so I've installed mprime in five separate directories on the shared file space, and let it allocate its own computer names. Yesterday I got fed up with trying to remember that CA1C7B916 was actually the machine called ouzo, so I stopped mprime on each machine, edited local.ini to change the name, and restarted mprime. Has this confused everything horribly? _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 31 May 2001 15:39:37 +0200 From: Steinar H. Gunderson [EMAIL PROTECTED] Subject: Mersenne: Re: Various ways of changing horses in mid-stream On Thu, May 31, 2001 at 02:13:27PM +0100, Thomas Womack wrote: This seems somehow inelegant, particularly in that my account report now says that I have an 8000MHz K6 machine called Tom_s_P4 ... what's the right way of doing it? If not getting credit is OK for you, you might consider using the PrimeNet manual check-out/-in forms. As another point, I have five Athlon/850 machines in the computer lab at college; so I've installed mprime in five separate directories on the shared file space, and let it allocate its own computer names. Yesterday I got fed up with trying to remember that CA1C7B916 was actually the machine called ouzo, so I stopped mprime on each machine, edited local.ini to change the name, and restarted mprime. Has this confused everything horribly? Possibly, yes -- but I don't think it's critical, as long as you didn't switch usernames, PrimeNet should still accept the result. However, the right thing to do this is (as far as I know) simply to edit the computer information from the mprime menu (mprime -m) -- if you do that, mprime will (again, as far as I know :-) ) tell the PrimeNet server about the change. /* Steinar */ - -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 31 May 2001 08:29:40 -0700 From: Aaron Blosser [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Various ways of changing horses in mid-stream As another point, I have five Athlon/850 machines in the computer lab at college; so I've installed mprime in five separate directories on the shared file space, and let it allocate its own computer names. Yesterday I got fed up with trying to remember that CA1C7B916 was actually the machine called ouzo, so I stopped mprime on each machine, edited local.ini to change the name, and restarted mprime. Has this confused everything horribly? Possibly, yes -- but I don't think it's critical, as long as you didn't switch usernames, PrimeNet should still accept the result. However, the right thing to do this is (as far as I know) simply to edit the computer information from the mprime menu (mprime -m) -- if you do that, mprime will (again, as far as I know :-) ) tell the PrimeNet server about the change. I've changed my computer names before just by editing the local.ini file. No problems... next time it updates the info on the server or checks in results, it'll reflect the changed name. And even if it didn't, no big deal anyway. _ Do You Yahoo!? Get
Mersenne Digest V1 #857
Mersenne Digest Tuesday, May 29 2001 Volume 01 : Number 857 -- Date: Fri, 25 May 2001 07:42:46 -0400 From: Alan Powell [EMAIL PROTECTED] Subject: Re: Mersenne: Bug? Hi Jeroen According to the Cunningham tables: 2^101-1 = 7432339208719 * 341117531003194129 2^101+1 = 3 * 845100400152152934331135470251 Are you sure you did not select the +1 option by mistake ? Regards Alan Powell At 06:30 AM 5/25/01, you wrote: Stage 1 complete. 25964568 transforms, 1 modular inverse. Time: 59.738 sec. (27838040173 clocks) P101 has a factor: 3 Cofactor is a probable prime! If my calculations are correct 2^101-1 = 2535301200456458802993406410751 To check if this is divisible by 3 add al digits and check if the sum is divisible by 3 Total of digits is 112 so 3 is not a factor. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 25 May 2001 13:31:02 +0100 From: Michael Bell [EMAIL PROTECTED] Subject: Re: Mersenne: Bug? Hi I was playing around with the client program. When I go to the advanced menu and choose ecm, there I fill in for exponent 101 and check the factor 2^N-1 box and click ok. After about a minute the program says to me : Stage 1 complete. 25964568 transforms, 1 modular inverse. Time: 59.738 sec. (27838040173 clocks) P101 has a factor: 3 Cofactor is a probable prime! If my calculations are correct 2^101-1 = 2535301200456458802993406410751 To check if this is divisible by 3 add al digits and check if the sum is divisible by 3 Total of digits is 112 so 3 is not a factor. You are correct that 2^101-1 does not have 3 as a factor, however, Prime95 was testing 2^101+1, this is why it says P101, which is divisible by 3 and the cofactor is indeed probable prime. I would guess you accidently selected the wrong option, if not then there is a bug where Prime95 is testing 2^n+1 instead of 2^n-1. Michael. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 29 May 2001 20:43:45 -0700 From: Luke Welsh [EMAIL PROTECTED] Subject: Mersenne: Back online(?) Hi everybody-- Gordon thinks that the list is back online. His DSL line was down from 10am Friday through 5pm Tuesday. - --Luke _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #857 **
Mersenne Digest V1 #855
Mersenne Digest Monday, May 21 2001 Volume 01 : Number 855 -- Date: Sat, 19 May 2001 10:55:59 -0400 From: =?iso-8859-1?Q?Roger_Gari=E9py?= [EMAIL PROTECTED] Subject: Mersenne: Fw: numeric hazards of high performance CPU design = Pentium 4 - constant speed problem I came about this information on degrading calculations after about 10 minutes of usage. I think it can help explain stange behavour on your test of Prime 95 for P4. Don't be confuse by the web page title. - Roger Gariépy :-) - :-( [EMAIL PROTECTED] - - Original Message - From: validlab [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Thursday, May 17, 2001 5:20 PM Subject: numeric hazards of high performance CPU design http://www.inqst.com/articles/athlon4/0516main.htm _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 19 May 2001 08:38:53 -0700 From: Timothy Luders [EMAIL PROTECTED] Subject: Re: Mersenne: Different results Hello Mersenne, George woltman wrote: This suggestion is actually a high priority for the next release. The error is probably caused by some driver or program initialization that isn't saving the FPU state properly. The error is benign as you found out. I think the main advantage of this feature is it will lead to slightly faster boot times and thereby improve prime95's reputation of not interfering with your everyday work. Glad to see this. 99% of errors form my computer are at boot usually after a new program install. I try to remember to uncheck Windows95 service when installing anything but sometimes it slips by. Timothy Luders replying form the digest _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 19 May 2001 16:52:22 +0100 (BST) From: Chris Jefferson [EMAIL PROTECTED] Subject: Re: Mersenne: Fw: numeric hazards of high performance CPU design = Pentium 4 - constant speed problem I just felt I had to say, that I am very disturbed by this. The idea of my CPU simply shutting down when it overheats is a sensible idea. This is much more dodgy, espicaly as there doesn't seem to be any way of finding out, short of lots of benchmarks, if your processor is doing this... :-( It also raises problems for prime95, as it looks like running prime95 will reduce your PC's speed by half. I am going to recieve a pentium 4 shortly, and although I shall try to send it back for an AMD processor, if I can't I shall run tests with prime95. However if these figures are true then it won't be searching for primes :-( Chris - -- Chris Jefferson, Girton College, Cambridge, CB3 0JG - --- http://mrjeff.webjump.com Don't bother, it's not worth looking at. On Sat, 19 May 2001, Roger Gariépy wrote: I came about this information on degrading calculations after about 10 minutes of usage. I think it can help explain stange behavour on your test of Prime 95 for P4. Don't be confuse by the web page title. Roger Gariépy :-) - :-( [EMAIL PROTECTED] - Original Message - From: validlab [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Thursday, May 17, 2001 5:20 PM Subject: numeric hazards of high performance CPU design http://www.inqst.com/articles/athlon4/0516main.htm _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 19 May 2001 16:24:55 -0400 From: George Woltman [EMAIL PROTECTED] Subject: Re: Mersenne: Fw: numeric hazards of high performance CPU design = Pentium 4 - constant speed problem Hi, At 04:52 PM 5/19/2001 +0100, Chris Jefferson wrote: I just felt I had to say, that I am very disturbed by this. The idea of my CPU simply shutting down when it overheats is a sensible idea. This is much more dodgy, espicaly as there doesn't seem to be any way of finding out, short of lots of benchmarks, if your processor is doing this... :-( Although I've not run LL tests for extended periods of times, I have never noticed the CPU throttling down by half. Time will tell if this is a significant problem or will only
Mersenne Digest V1 #854
Mersenne Digest Saturday, May 19 2001 Volume 01 : Number 854 -- Date: Wed, 16 May 2001 19:52:48 -0500 From: Ken Kriesel [EMAIL PROTECTED] Subject: Mersenne: Spacing between mersenne primes At 10:56 AM 5/16/2001 -, Brian J. Beesley [EMAIL PROTECTED] wrote: Another point - we're coming up to the second anniversary of the discovery of M38(?) - I think we're overdue to find another one! It would be nice to find another soon. But I don't think we're overdue. Long ago in Internet time I wrote: Date: Thu, 29 Jan 1998 22:57:31 -0600 In mersenne primality testing, exponents double in magnitude are much more than double the work. For prime95 or the related versions, each iteration takes about 2.1 times as long as an iteration for half the FFT length, and there are twice as many iterations to perform, per exponent. The odds of a number being prime diminishes as the magnitude increases. Twice the FFT length is usable up to not quite twice the exponent. An interval of n to 2n contains nearly twice as many exponents as the interval 1/2 n to n. In either of these intervals we expect based on experience, to find about the same number of mersenne primes on the average. (The actual rate of occurrence seems to be a little bit in our favor for finding more primes in higher intervals, but it's slight.) That makes about 3 factors of 2. I think to maintain a constant rate of discovery of new primes, we would need to maintain about an 8 or 9-fold increase of computing resources per period of exponent doubling. Since exponent doubling has occurred in about the past year, most of this must come in rapid growth in the cpu pool, both by upgrades and by new membership. Otherwise we can expect to droop back to a lower discovery rate. On average there are less than 2 mersenne primes per exponent doubling: 36 / [ln(2976221)/ln(2)] = 1.67 mersenne primes per doubling of exponent, or about 37 / [ln(~300)/ln(2)] = 1.72 Mp's per doubling of p (though we may have yet to find one in p 2976221, or slightly above!) In the long run the present discovery rate is unsustainable. Even if we do drop back to a discovery rate of one per two years, from the recent ~2 per year, we will have moved this area ahead by years from its old curve. (The discovery rate was about 1 per 2 years over the past 20 year interval and for the past 40 year interval.) Our experience described on http://www.mersenne.org/history.htm bears this out. And there is no particular reason to expect the time interval, or the spacing between mersenne primes on a log or linear scale to be uniform. It should vary about the expected curve. Ken Kriesel _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 17 May 2001 00:39:11 -0500 From: Jeramy Ross [EMAIL PROTECTED] Subject: Re: Mersenne: SUMOUT errors A interesting note, and I forgot to include this in my original post, but the computer that I encountered the illegal sumouts on was a 500MHz K6 PC. Perhaps this is a problem when running those software modems on a K6 based machine?? - - Jeramy Original Message - From: Steve [EMAIL PROTECTED] For what it's worth, I have had the exact same problem getting illegal sumouts when using the modem on this 475Mhz K6 PC. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 18 May 2001 01:17:45 +1000 From: Steve Phipps [EMAIL PROTECTED] Subject: Re: Mersenne: ECM Question... While we're on the subject, can someone explain how to derive the group order for factors found using ECM? I've been carrying out ECM on an old PC for almost a year now, and I'd like to be able to derive, and factorise, the group orders for the factors that I've found. I've been making an effort to understand the maths, and I'm getting there slowly, but I've found nothing yet that explains how to derive the group orders. If my understanding is correct, you would need to know the equations used by mprime to derive the co-ordinates of the starting point for each curve. Anyway, if someone could explain how to derive the group order, or point me in the right direction, I'd be very grateful. Regards, Steve If the sigma is the same, then a curve with B1=25 will find any factor that a curve with B1=5 finds. When you run 700 random curves at B1=25, you might theoretically miss a factor that someone else finds with B1=5, if he gets a lucky sigma so that the group order is very smooth. But in general, using the same number of curves, the higher bound should find all the factors that the lower
Mersenne Digest V1 #853
Mersenne DigestWednesday, May 16 2001Volume 01 : Number 853 -- Date: Tue, 15 May 2001 20:56:20 -0400 (EDT) From: Jason Stratos Papadopoulos [EMAIL PROTECTED] Subject: Re: Mersenne: GIMPS accelerator? On Tue, 15 May 2001, Gareth Randall wrote: Also, any code would be very hardware specific, and may only work if the display was not displaying, say, a desktop. However, if someone could implement it, it could provide the *ultimate* in Mersenne related screen savers! What you'd see on the screen would be the actual calculations themselves taking place before your eyes, and with no overheads for displaying it either! This question pops up every once in a while. A few years ago I looked through a postscript manual wondering how difficult it would be to build a postscript file that crunched RC5 keys when a printer tried to render it. The latest bleeding edge graphics cards are programmable to a limited degree (am I thinking of the ATI Radeon here?) but not nearly programmable enough, I'm sure. Heck, at least these ideas have a better chance than the guys who want to crack the programming on kids' toys to make them crunch RC5 keys :) jasonp _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 16 May 2001 01:32:15 + (GMT) From: Russel Brooks [EMAIL PROTECTED] Subject: Re: Mersenne: GIMPS accelerator? John R Pierce wrote: Virtually all GPU's in use today are fixed function hard wired graphics accelerators. There's no way to use them for general purpose computational use. Also, there's no APIs, and each chip vendor has a radically different architecture. Too bad, the idea might also have given us an interesting screen saver as a side effect! :-) Cheers... Russ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 15 May 2001 20:58:34 -0500 From: Jeramy Ross [EMAIL PROTECTED] Subject: Re: Mersenne: SUMOUT errors I don't really know how much help this will be since I don't know your exact situation and am not a expert by any means, but here goes! First, the software modem may be a culprit. I have had problems with ones of the HSP variety. Most show up as 'HSP Micromodem56' or something very similar on your system. Most of these modems also use a chipset manufactured by PCTel. Fairly stable, but use a nice chunk of CPU time when online, and I have received errors when I am checking email and/or surfing the web while using this type of modem. I have no hard evidence to tie this modem to the errors, but all errors happened when I was using that modem or soon after (I hooked up a external modem just to see if the same would happen with it and I did not receive errors when using it). I have no idea if you have a modem similar to that one or not, but it may be the problem. Also, the electrical environment may be vastly different. I am assuming that where you had your computer was at school, and it is now at home. At my home, I have problems with various utility problems, and have been told by others that utility problems could cause such errors. I invested in a UPS with line conditioning to hopefully control some of those problems. Maybe one of these two things could be your problem.. I wish you the best of luck in finding and fixing the problem! - - Jeramy _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 15 May 2001 19:21:08 -0700 From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: GIMPS accelerator? This question pops up every once in a while. A few years ago I looked through a postscript manual wondering how difficult it would be to build a postscript file that crunched RC5 keys when a printer tried to render it. postscript is essentially forth, after all. Trouble is, most postscript interpreters are pretty damn slow. The latest bleeding edge graphics cards are programmable to a limited degree (am I thinking of the ATI Radeon here?) but not nearly programmable enough, I'm sure. NVIDIA's chips are semi programmable too, but a big hurdle is lack of documentation on the 3D rendering engine. That stuff is trade secret. I *do* suspect you could use the geometry engine (aka Transformation Lighting and Projection) to do large numbers of fixed point 3x3 vector-matrix dot products with limited precision rather quickly. The question is, how useful would this be? The pipeline is probably
Mersenne Digest V1 #851
Mersenne Digest Monday, May 14 2001 Volume 01 : Number 851 -- Date: Mon, 14 May 2001 16:14:07 -0400 From: Joshua Zelinsky [EMAIL PROTECTED] Subject: Re: Mersenne: Re: 26 exponents Nathan Russel wrote: Are you suggesting that, every time George offers exponents to the members of this mailing list, he should send out a newsletter to every participant - guaranteeing hundreds or thousands of replies for him to deal with? I think there may be no good solution to this. Have the e-mails go to an account linked to the server. It would take a little work, but the whole process could be automated. Regards, Joshua Zelinsky [EMAIL PROTECTED] _ Get your FREE download of MSN Explorer at http://explorer.msn.com _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 14 May 2001 20:23:45 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Re: 26 exponents On 14 May 2001, at 8:45, Nathan Russell wrote: First of all, as Jud notes, the 'elitism' is already there, in that different machines get treated differently in the assignments that they are given. Sorry, I don't buy that. Every system has exactly the same chance of picking up any given assignment; it's a matter of the time at which you make the request. And you _can_ override the assignment type which would be the default for your system, if you wish to do so. Even readers of this list get opportunities to acquire exponents or prebeta-test software, etc., that are not available to the unwashed masses. AFAIK everyone is entitled to subscribe to this list, whether they participate by running assignments or not. Additionally, GIMPS, unlike most other projects, has exponents taht are 'better' than others. In the absence of completed tests, small exponents are more likely to be prime than larger ones, as well as taking less effort to test. However, note that a considerable number of users have voluntarily chosen to run 10 million digit range exponents, thus reducing the probability that they will discover a prime. The increased reward for being successful counterbalances the reduced chance of success. There is also a theoretical difference between those exponents congruent to 1 modulo 4 and those congruent to 3 modulo 4. However I believe that this is due to the fact that one of these groups has a larger probability of having a small factor; thus this irregularity is removed by the time that LL testing begins. Secondly, if - when I ask the server to give me whatever kind of work makes most sense - it gives me something else, whether out of spurious concern for my feelings or for any other reason, then not only are the programmers betraying my trust in them, they are also indicating that they don't trust me to ask for what I want. I agree. Either you allow people to choose the type of work they want, or you tell people plainly that you will select for them the type of work you will ask them to do. Either works, but a mixture is inconsistent. Note that an exponent given out for triple-checking has a microscopic chance of being prime (something like two in one billion), since it must 1. Be prime (once chance in 60,000-70,000) and 2. Have been missed by both previous tests (1 in 100 for each). NO! Conditional probability: if we need a third LL test run, it is because at least one of the other two _must_ be in error. So the probability of finding a prime on the third LL test run is (about) one half the probability of finding a prime on the second LL test run - - irrespective of the error rate, provided it is small. People need to be informed about departures from documented practice. Are you suggesting that, every time George offers exponents to the members of this mailing list, he should send out a newsletter to every participant - guaranteeing hundreds or thousands of replies for him to deal with? I think there may be no good solution to this. Clearly this is ridiculous. I don't have a problem with George offerring a few exponents selectively through this list, because the list does not have a closed membership. The only sane alternative is to wait for deadline critical assignments to complete in the normal way - something which some people have vociferously objected to. Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 14 May 2001 20:23:45 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Pentium
Mersenne Digest V1 #852
Mersenne Digest Tuesday, May 15 2001 Volume 01 : Number 852
--
Date: Mon, 14 May 2001 23:33:48 +0200
From: Steinar H. Gunderson [EMAIL PROTECTED]
Subject: Re: Overriding assigned exponent type (was Re: Mersenne: Re: 26 exponents)
On Mon, May 14, 2001 at 02:00:02PM -0700, Aaron Blosser wrote:
I fear that many folks may not be aware of the list, or find
that subscribing seems too hard (odd as that may sound to us experts :)
Or perhaps being set back by the description of an in-depth discussion
about Mersenne primes... ;-) When people start throwing the maths
around, I feel like I should take more maths soon :-P
Anyhow, no critique, but perhaps this _isn't_ a mailing list for the
general user. I personally like it, but the average SETI@Home `convert'
might not. Perhaps we could have a general `users' list instead?
/* Steinar */
- --
Homepage: http://members.xoom.com/sneeze/
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
--
Date: Tue, 15 May 2001 10:43:00 -0400
From: Nathan Russell [EMAIL PROTECTED]
Subject: Re: Overriding assigned exponent type (was Re: Mersenne: Re: 26 exponents)
On Mon, 14 May 2001 23:33:48 +0200, Steinar H. Gunderson wrote:
On Mon, May 14, 2001 at 02:00:02PM -0700, Aaron Blosser wrote:
I fear that many folks may not be aware of the list, or find
that subscribing seems too hard (odd as that may sound to us experts :)
Or perhaps being set back by the description of an in-depth discussion
about Mersenne primes... ;-) When people start throwing the maths
around, I feel like I should take more maths soon :-P
I'd tend to agree - the list is, at times, too in-depth for my
understanding, though it's lead me to do a fair amount of research on
my own. There are still discussions about CPU architecture, as well
as off-topic discussions about systems adminstration, that I don't
pretend to follow, but I've found that I've learned a lot reading
through those discussions.
As for a 'users' mailing list, I don't feel that that's necessary; if
'ordinary users' want to get on the list, they can simply read only
those threads that they understand and are interested in. The list
isn't so high-volume as to make that in any way prohibitive.
Nathan
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
--
Date: Tue, 15 May 2001 16:48:14 +0100
From: Kevin Edge [EMAIL PROTECTED]
Subject: Mersenne: Yeti at Home
You may be interested (briefly) in a new distributed computing
project that I have come across - Yeti at Home. Details at:
http://www.phobe.com/yeti/index.html
Kevin Edge
{:)}
- ---
Kevin Edge - [EMAIL PROTECTED]
- ---
The opinions herein are my own and,
unless explicitly stated,
may not represent those of
Northgate Information Systems
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
--
Date: Tue, 15 May 2001 18:12:39 +0200
From: Paul Landon [EMAIL PROTECTED]
Subject: Re: Mersenne: games one can play with genuine composites
If a prime Q | M_C
then Order(2,Q) | C ;but not 1
Order(2,Q) | Q-1
F:=GCD(C,Q-1) != 1
F will either be C or one of it's divisors.
If Order(2,Q)==C then it has almost zero information
to tell us anything about the factors of C.
If C has 2 factors P0 P1 then the product of factors
with Order == C is M_C/(M_P0.M_P1)
with Order == P1 is M_P1
Order == P0 is M_P0
(For more than 2 factors of C, Pofwo(C) is recursively
defined as M_C / all the pofwos of the divisors of C).
I would expect the probability that a factor of M_C
has these orders to be a non-decreasing function of these
products.
An approximation for the probabilities could be just the
ratio of these products.
Sadly for composites such as M727 which guesses have as
having a small number of factors and it is known that the
smallest factor is bigger than a decent bound, F will
equal M727 nearly all the time, and rarely will a factor
be found. There is also the rare case where the order of
Q = M_C but F=M_C
The distribution of Mersenne Divisors is such that small
Q will tend to have a smaller order, and any Q=2M_C
will not have order M_C.
If you are only searching for factors of M_C of the form
KC+1 then these will always have F=M_C and tell us nothing
about the factors of C. The only factors of M_C that help
with factoring C are those not of the form KC+1.
Stating the obvious, M_C
Mersenne Digest V1 #850
Mersenne Digest Monday, May 14 2001 Volume 01 : Number 850 -- Date: Sun, 13 May 2001 11:03:50 +0200 From: mohk [EMAIL PROTECTED] Subject: Re: Mersenne: Pentium 4 owners - pre-beta prime95 release available At 03:02 13.05.2001, you wrote: Hi, The P4-optimized version of prime95 is ready for adventurous users to try out. Ordinarily I would not release a trial version at this point, but I'm sure P4 owners are itching for a 3x performance boost. If you do not own a P4, then DO NOT DOWNLOAD THIS VERSION. It contains no new features and your results will be marked invalid if we later discover a bug in this code. Don't you say, this code enhances the Athlon as well? regards, Mohk _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 13 May 2001 12:13:28 +0200 From: Steinar H. Gunderson [EMAIL PROTECTED] Subject: Mersenne: Re: Pentium 4 owners - pre-beta prime95 release available On Sun, May 13, 2001 at 11:03:50AM +0200, mohk wrote: Don't you say, this code enhances the Athlon as well? No, it doesn't. It's that much faster mainly because it utilizes the SSE2 instructions that are new on the P4, which the Athlon doesn't have (yet). /* Steinar */ - -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 13 May 2001 11:48:48 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Pentium 4 owners - pre-beta prime95 release available On 12 May 2001, at 21:02, George Woltman wrote: If you try out this version, please let me know of any problems. It would be helpful if you ran double-check assignments for a few weeks. If anyone wants to be a bit more adventurous than taking ordinary PrimeNet DC assignments, I have a limited number of exponents which will require double-checking at some stage for which interim residues at 1 million iteration checkpoints are available. The point here is that if you also set the program for million iteration checkpoints (InterimFiles=100 in prime.ini) you will be able to catch any discrepancies early without having to continue the run to the end. (Of course there is a chance that my checkpoint residues may not be correct - but the systems they are running on seem to be pretty reliable!) The exponents for which I have interim residues are as follows: 7056503, 7092307, 7094839, 7477177, 7731131, 7731259, 7871953, 7927697, 7979819, 8164349, 8167919, 8242327, 8255881, 8369941, 8380621, 8434523, 8549371, 8555881, 8563109, 8573107, 8615273, 8650927, 8655991, 8715337, 8719367, 8767471, 8900161, 8907359, 9057403, 9117209, 9189533, 9443311, 9475097, 9607691, 9617929, 9743639, 9743803, 10068077, 10126621, 10319891, 10386067, 10809893, 11173153, 11561909, 11570227, 11636479, 11772809, 12141223 12450397. If anyone is interested in testing any of these with the P4 code, let me know around what size exponent you're willing to take on; I'll reply by email allocating a unique exponent with a list of the appropriate million iteration interim residues. Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 13 May 2001 11:57:41 -0500 (CDT) From: [EMAIL PROTECTED] Subject: Mersenne: Re: story of scientists travelling by train Brian J. Beesley wrote: Mathematician (after long pause): No, in Scotland there exists at least one sheep, at least one side of which appears to be black. What do you mean, long pause ??? :-) Richard Woods _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 13 May 2001 12:10:38 -0500 (CDT) From: [EMAIL PROTECTED] Subject: Mersenne: Re: story of scientists travelling by train Brian J. Beesley wrote: As the train crosses the border into Scotland, they observe a black sheep in an otherwise empty field. (* snip *) Mathematician #2 (after reading story): Does that mean that the black sheep is both the additive and the multiplicative identity? :-) Richard Woods _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne Digest V1 #849
Mersenne Digest Sunday, May 13 2001 Volume 01 : Number 849 -- Date: Sat, 12 May 2001 08:06:41 +0200 From: [EMAIL PROTECTED] (Achim Passauer) Subject: Mersenne: missing exponents? This is a multi-part message in MIME format. - --=_NextPart_000_0006_01C0DABA.7A854360 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Hi all, I was a bit astonished this morning (0500 UTC) when I saw that about = 50.000 exponents have been cleared since the last database synch. A few = days ago there were about 53.000 to 54.000 of them. Were have 3.000 to = 4.000 exponents gone? Any explanation? Regards Achim - --=_NextPart_000_0006_01C0DABA.7A854360 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC -//W3C//DTD HTML 4.0 Transitional//EN HTMLHEAD META http-equiv=3DContent-Type content=3Dtext/html; = charset=3Dwindows-1252 META content=3DMSHTML 5.50.4522.1800 name=3DGENERATOR/HEAD BODY bgColor=3D#ff DIVFONT size=3D2Hi all,/FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2I was a bit astonished this morning (0500 UTC) when = I saw that=20 about 50.000 exponents have been cleared since the last database synch. = A few=20 days ago there were about 53.000 to 54.000 of them. Were have 3.000 to = 4.000=20 exponents gone? Any explanation?/FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2RegardsBRAchim/FONT/DIV/BODY/HTML - --=_NextPart_000_0006_01C0DABA.7A854360-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 12 May 2001 10:35:46 +0200 From: Dieter Schmitt [EMAIL PROTECTED] Subject: Re: Mersenne: missing exponents? This is a multi-part message in MIME format. - --=_NextPart_000_0013_01C0DACF.4DCADDC0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Hi Achim, have a look a the available exponents for double checking. George has made several thousend new exponents available. Maybe the new = exponents hadn't been double checked before or previous double checking = results didn't match. Therefore he had to do a 'small synchronization' = at some ranges to remove older double checking results. Regards Dieter -Urspr=FCngliche Nachricht-=20 Von: Achim Passauer=20 An: [EMAIL PROTECTED]=20 Gesendet: Samstag, 12. Mai 2001 08:06 Betreff: Mersenne: missing exponents? Hi all, I was a bit astonished this morning (0500 UTC) when I saw that about = 50.000 exponents have been cleared since the last database synch. A few = days ago there were about 53.000 to 54.000 of them. Were have 3.000 to = 4.000 exponents gone? Any explanation? Regards Achim - --=_NextPart_000_0013_01C0DACF.4DCADDC0 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC -//W3C//DTD HTML 4.0 Transitional//EN HTMLHEAD META http-equiv=3DContent-Type content=3Dtext/html; = charset=3Diso-8859-1 META content=3DMSHTML 5.50.4522.1800 name=3DGENERATOR STYLE/STYLE /HEAD BODY bgColor=3D#ff DIVFONT size=3D2Hi Achim,/FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2have a look a the available exponents for double=20 checking./FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2George has made several thousend new exponents=20 available.nbsp; Maybe the new exponents hadn't been double checked = before=20 ornbsp;previous double checking results didn't match.nbsp;Therefore he = had to=20 do a 'small synchronization' at some ranges to remove older double = checking=20 results./FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2Regards/FONT/DIV DIVFONT size=3D2Dieter/FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV BLOCKQUOTE dir=3Dltr=20 style=3DPADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #00 2px solid; MARGIN-RIGHT: 0px DIV style=3DFONT: 10pt arial-Urspr=FCngliche Nachricht- = /DIV DIV=20 style=3DBACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = blackBVon:/B=20 A [EMAIL PROTECTED]=20 href=3Dmailto:[EMAIL PROTECTED];Achim Passauer/A /DIV DIV style=3DFONT: 10pt arialBAn:/B A = [EMAIL PROTECTED]=20 href=3Dmailto:[EMAIL PROTECTED];[EMAIL PROTECTED]/A /DIV DIV style=3DFONT: 10pt arialBGesendet:/B Samstag, 12. Mai 2001 = 08:06/DIV DIV style=3DFONT: 10pt arialBBetreff:/B Mersenne: missing=20 exponents?/DIV DIVFONT size=3D2/FONTFONT size=3D2/FONTFONT = size=3D2/FONTFONT=20 size=3D2/FONTFONT size=3D2/FONTBR/DIV DIVFONT size=3D2Hi all,/FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2I was a bit astonished this morning (0500 UTC) = when I saw=20 that about 50.000 exponents have been cleared since the last database
Mersenne Digest V1 #848
Mersenne Digest Friday, May 11 2001 Volume 01 : Number 848 -- Date: Wed, 9 May 2001 17:54:44 -0500 From: C. Daniel Sheets [EMAIL PROTECTED] Subject: Mersenne: Team Account Question I presently have 13 computers setup under my individual account. These computers are used by various people but I have control of them as to who uses them, what software is loaded, etc. My questions are: What would I have to do to change my account to a team account? What are the benefits of team accounts? Is status reporting different for team accounts? Thanks in advance for any answers, Dan _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 12 May 2001 08:06:41 +0200 From: [EMAIL PROTECTED] (Achim Passauer) Subject: Mersenne: missing exponents? This is a multi-part message in MIME format. - --=_NextPart_000_0006_01C0DABA.7A854360 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Hi all, I was a bit astonished this morning (0500 UTC) when I saw that about = 50.000 exponents have been cleared since the last database synch. A few = days ago there were about 53.000 to 54.000 of them. Were have 3.000 to = 4.000 exponents gone? Any explanation? Regards Achim - --=_NextPart_000_0006_01C0DABA.7A854360 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC -//W3C//DTD HTML 4.0 Transitional//EN HTMLHEAD META http-equiv=3DContent-Type content=3Dtext/html; = charset=3Dwindows-1252 META content=3DMSHTML 5.50.4522.1800 name=3DGENERATOR/HEAD BODY bgColor=3D#ff DIVFONT size=3D2Hi all,/FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2I was a bit astonished this morning (0500 UTC) when = I saw that=20 about 50.000 exponents have been cleared since the last database synch. = A few=20 days ago there were about 53.000 to 54.000 of them. Were have 3.000 to = 4.000=20 exponents gone? Any explanation?/FONT/DIV DIVFONT size=3D2/FONTnbsp;/DIV DIVFONT size=3D2RegardsBRAchim/FONT/DIV/BODY/HTML - --=_NextPart_000_0006_01C0DABA.7A854360-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #848 **
Mersenne Digest V1 #847
Mersenne Digest Wednesday, May 9 2001 Volume 01 : Number 847 -- Date: Sun, 6 May 2001 21:55:25 -0600 From: Matt Goodrich [EMAIL PROTECTED] Subject: RE: Mersenne: Slow CPU's in a Proliant 2500 Thanks for the response Ethan, it was quite helpful. Yes I did set the type and speed in Prime 95. I wish it was something obvious like that! The indexing service was set to manual and is now disabled. No change in times. I wasn't aware that running 2 instances on a dual machine would run 30% to 40% slower than a single instance (if I understand you correctly?) It looks like I may just have to live with it. I am loathe to change those chips when I am not sure it will help. Also, I'm not even sure I will be able to find them, even if I was inclined to change them. I will try your suggestion of running a double check on 1 CPU and LL test on the other, when these double checks are done. Thanks again, Matt - -Original Message- From: Ethan Hansen [mailto:[EMAIL PROTECTED]] Sent: Sunday, May 06, 2001 8:01 PM To: [EMAIL PROTECTED] Subject: RE: Mersenne: Slow CPU's in a Proliant 2500 Matt, Sorry for raising the obvious, but have you changed both the CPU type and speed values under the Prime95 Options-CPU menu? Another item to check are that you have disabled the blasted indexing service. It could explain the slight CPU time leakage you are seeing. That said, the ratio I typically see between Prime95 iteration times on a dual processor system with two instances vs. only one running is in the 1.3-1.4x range; i.e. the difference between your times of 0.448 and 0.325. I have seen a slight degradation of iteration time/MHz when upgrading from 500 to 1GHz processors, but not as much as you report. A way to boost overall throughput is to run double checking (with it's smaller memory footprint) on one CPU, and primality tests on the other. Regards, Ethan - -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Matt Goodrich Sent: Sunday, May 06, 2001 5:26 PM To: [EMAIL PROTECTED] Subject: Mersenne: Slow CPU's in a Proliant 2500 I have just upgraded a Proliant 2500 from dual PPro 200's to dual Pentium II 333 overdrive processors. According to Intel's website this is supported. Also Compaq offers this upgrade. Now before I upgraded, I was running double check's on 2 exponents, 668. I was getting about .515 second iteration times. Now that I have upgraded, I am only getting .448 second iteration times. Yes, the affinity is set properly. [SNIP] Interesting note here. If I run just 1 copy of Prime on either CPU I get .325 second iteration times. It doesn't matter which copy of the program or which CPU I run it on. It is only when I run both copies that it slows down to .448 seconds. BTW I am running Windows 2000 Server with the latest SSD from Compaq. [SNIP] Any thoughts or suggestions would be appreciated. Matt _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 07 May 2001 02:04:23 -0400 From: Sandy Harris [EMAIL PROTECTED] Subject: Re: Mersenne: Slow CPU's in a Proliant 2500 Matt Goodrich wrote: I have just upgraded a Proliant 2500 from dual PPro 200's to dual Pentium II 333 overdrive processors. ... Now before I upgraded, I was running double check's on 2 exponents, 668. I was getting about .515 second iteration times. Now that I have upgraded, I am only getting .448 second iteration times. Might it just be the effect of slower cache? As I recall, the numbers were: P Pro256 or 512K one CPU clock to deliver data P II 512 K two Celeron 128 K one and on some tasks, Celeron outperforms P II at the same clock because of this. If the process is cache-bound and key data fits in both caches, this gives about the right numbers. P II cache runs at 333/2 which is to 200 roughly as .448 is to .515. Alternately. do you just need a differently optimised version of the code to get the best out of your P IIs? _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 7 May 2001 07:55:56 +0200 From: tom ehlert [EMAIL PROTECTED] Subject: Mersenne: Slow CPU's in a Proliant 2500 Hi Matt, Now that I have upgraded, I am only getting .448 second iteration times. If I run just 1 copy of Prime on either CPU I get .325 second iteration As I have the same problem, some hints: I have a dual P700 (MSI 694D motherboard, PC133 RAM). running Prime twice, I get .340 (at 12xx), running only one copy, I get 270. If the second Prime is set for factoring, the first
Mersenne Digest V1 #846
Mersenne Digest Sunday, May 6 2001 Volume 01 : Number 846 -- Date: Sat, 31 Mar 2001 07:28:05 -0600 From: Richard B. Woods [EMAIL PROTECTED] Subject: Re: Mersenne: Countdown is slowing In reply to fay aron charles [EMAIL PROTECTED]: It shows that the countdown to testing all exponents below M(6972593) at least once is 33. I see this a very large milestone. Last week the countdown was 34, and the week before that it was 34. Patience. All earlier milestones were passed, and this one will be achieved and passed also. I would assume the slow progress is because the last few exponents are reserved by people with very slow processors who still update with the server at least every 60 days. I have one of those exponents reserved, and am actively conducting its L-L test on my P75 even as I read your message and compose this response. With this processor I have completed L-L testing on more than 30 Mersenne numbers (in addition to factoring work on about that many others) since I joined GIMPS. Never have I delayed the achievement of a GIMPS milestone. Never -- not once -- have I quit any test without immediately properly checking the exponent back in. In a few cases, I stopped testing an exponent and checked it back in because a revision in my private theory about the occurrence of Mersenne primes indicated that there was no chance for that candidate to be prime. Why do I participate? The slim chance of fame in case I discover a Mersenne prime. Even though my private theory about the occurrence of Mersenne primes predicts that exponents other than the ones I have reserved through GIMPS have higher chances of being prime, I continue to cooperate with GIMPS by working with exponents I am assigned, instead of poaching by testing exponents that are assigned to other participants. Could these last few exponents be assigned for double checking now? It would at least satisfy my curiosity. ... and, by allowing someone with a much faster processor to L-L test my assigned exponent, it would also allow that someone to determine whether the number under test is prime, or not, _before I do_. I.e., your proposal would rob me of my chance for fame by breaking the current contract that my reservation means that only I have the opportunity for potential fame in discovering that my M(6xx) is prime, as long as I fulfill my part by making reasonable progress. If that were allowed, then why should I continue contributing to GIMPS at all ... ... when my just-arrived Athlon 1.2 GHz (that's 16 * 75 MHz) processor is ready to join in? If GIMPS breaks its contract with me, I'll take my new fast processor elsewhere. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 02 May 2001 07:42:15 -0700 From: Gary Untermeyer [EMAIL PROTECTED] Subject: Re: Mersenne: Countdown is slowing Greetings, Hey Richard! I applaud your patience and perserverence. It's not so much how fast a GIMPS computer is, but how well its owner keeps it on track. Milestones would be reached much quicker if all had the same attitude toward responsibility. I currently have over 300 exponents tested, many of them done on a P100. It's still doing double checking work while my new P733 (well, relatively new) cranks away on other things for GIMPS. Keep on truckin', Gary _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 6 May 2001 18:26:21 -0600 From: Matt Goodrich [EMAIL PROTECTED] Subject: Mersenne: Slow CPU's in a Proliant 2500 I have just upgraded a Proliant 2500 from dual PPro 200's to dual Pentium II 333 overdrive processors. According to Intel's website this is supported. Also Compaq offers this upgrade. Now before I upgraded, I was running double check's on 2 exponents, 668. I was getting about .515 second iteration times. Now that I have upgraded, I am only getting .448 second iteration times. Yes, the affinity is set properly. I have set the switches on the I/O board for 66/333 speed. I believe my problem stems from having the wrong ROM chips. The server, when booting, says the BIOS is version E24 which is associated with the PPro 200 processors. I went to Compaq's web site and found that the E50 version is for PII 333's. Downloaded the ROMPaq but it will not flash. It says there isn't a valid ROM Image on the floppy disk for the installed device. After searching Compaq's web site (with their lousy search engine I might add) I found an article that say's I probably need to replace the physical ROM chips. Now for my question. Has anyone here
Mersenne Digest V1 #845
Mersenne Digest Tuesday, May 1 2001 Volume 01 : Number 845 -- Date: Sat, 28 Apr 2001 17:18:14 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne Digest V1 #843 On 28 Apr 2001, at 0:57, [EMAIL PROTECTED] wrote: Question (deep) - if we did discover a factor of 2^(2^727-1)-1, would that help us to find a factor of 2^727-1 ? The reason for asking this question was twofold: firstly, to find out whether it _might_ be possible to know a factor of 2^c-1 without knowing a factor of c, and secondly, if this statement is not true, (in other words, if finding a factor of M(M(p)) automatically leads to the derivation of a factor of M(p)) to possibly find a factor of the recalcitrant number M(727) by attempting to factor M(M(727)), which probably hasn't had much effort expended on it. Yet. I am skeptical too. Show us how the factors 131009 of M_(M11) = 2^(2^11 - 1) - 1 724639 of M_(M11) 285212639 of M_(M23) lead to factorizations of M11 and M23. Why don't the factors 231733529 of M_(M17) 62914441 of M_(M19) lead to similar factorizations of M17 and M19? The obvious answer here is that 11 and 23 are 3 mod 4 Sophie Germain primes, whereas neither 17 nor 19 are. I tinkered around a bit with the algebra but wasn't able to come up with a formal justification for this distinction. The point of course is that there is a formal proof that, if a prime p is congruent to 3 modulo 4 and 2p+1 is also prime, then 2^p-1 is divisible by 2p+1 - which makes searching for a factor of M(p) by trying to factor M(M(p)) somewhat pointless! With c = 2^727 - 1, 2^751 - 1, 2^809 - 1, 2^997 - 1, 2^1051 - 1, I looked for factors 2*k*c + 1 of 2^c - 1, but found none with k = 2. I invite those with a special search program for M_(M127) factors to search these further. None of 727, 751, 809, 997 1051 are 3 mod 4 S-G primes (else they wouldn't be on the factors wanted lists!) Regards Brian Beesley 1775*2^332181+1 is prime! (10 digits) Discovered 22-Apr-2001 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 29 Apr 2001 09:33:24 +0200 (MET DST) From: [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne Digest V1 #843 Brian J. Beesley [EMAIL PROTECTED] wrote, in response to my earlier message The point of course is that there is a formal proof that, if a prime p is congruent to 3 modulo 4 and 2p+1 is also prime, then 2^p-1 is divisible by 2p+1 - which makes searching for a factor of M(p) by trying to factor M(M(p)) somewhat pointless! With c = 2^727 - 1, 2^751 - 1, 2^809 - 1, 2^997 - 1, 2^1051 - 1, I looked for factors 2*k*c + 1 of 2^c - 1, but found none with k = 2. I invite those with a special search program for M_(M127) factors to search these further. None of 727, 751, 809, 997 1051 are 3 mod 4 S-G primes (else they wouldn't be on the factors wanted lists!) Then I challenge readers to show how to discover the factor 11447 of 2^97 - 1 given the factor 1800*(2^97 - 1) + 1 of M(M97) 97 is not 3 mod 4. Let c be a large positive integer. Given k with 1 = k = 2, the chance that 2*k*c + 1 is a prime divisor of 2^c - 1 is about (1/(2*k)) * (2/ln(2*k*c)) = 1/(k * ln(2*k*c)) Integrate this from k = 1 to k = 2. An antiderivative is ln(ln(2*k*c)). The integral is ln(ln(4*c)) - ln(ln(2*c)) = ln( ln(4*c) / ln(2*c) ) = ln(1 + ln(2) / ln(2*c) ) For c as large as 10^8, the quotient ln(2) / ln(2*c) exceeds 0.5, giving an estimated ln(1.5) ~= 0.4 factors with 1 = k = 2. For c = 2^e - 1 with large e, we estimate 14.2/(e + 1) factors with k in this range. This is only 0.02 factors when e = 727, so it should not be surprising that my search was unsuccessful. Extending the search to k 10^8 will approximately double our chance of success. Peter Montgomery [EMAIL PROTECTED] - --JAA22954.988529496/hera.cwi.nl-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 1 May 2001 07:55:51 -0500 From: fay aron charles [EMAIL PROTECTED] Subject: Mersenne: Countdown is slowing I've been following the status of gimps recently with the following page: http://mersenne.org/status.htm It shows that the countdown to testing all exponents below M(6972593) at least once is 33. I see this a very large milestone. Last week the countdown was 34, and the week before that it was 34. I would assume the slow progress is because
Mersenne Digest V1 #844
Mersenne DigestSaturday, April 28 2001Volume 01 : Number 844 -- Date: Thu, 26 Apr 2001 06:34:07 +0200 (MET DST) From: Hans Riesel [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #843 Hi everybody, If 2^p-1 is known to be composite with no factor known, then so is 2^(2^p-1)-1. Hans Riesel _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 26 Apr 2001 01:02:23 -0400 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne Digest V1 #843 On Thu, 26 Apr 2001 06:34:07 +0200 (MET DST), Hans Riesel wrote: Hi everybody, If 2^p-1 is known to be composite with no factor known, then so is 2^(2^p-1)-1. For that matter, the same argument can be made with regard to 2^(2^R-1)-2 for some RSA factoring challange number R, and probably many other categories of numbers - even excluding the huge numbers of genuine composites generated by GIMPS and other such projects. It would be interesting to discuss whether numbers of this form can be validly seen to have passed a compositness test... Nathan _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 25 Apr 2001 22:38:32 -0700 From: Spike Jones [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne Digest V1 #843 Hans Riesel wrote: Hi everybody, If 2^p-1 is known to be composite with no factor known, then so is 2^(2^p-1)-1. Hans Riesel It has been a long time since I have seen a more elegant argument ender than this. Thanks Hans! spike _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 26 Apr 2001 06:53:56 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne Digest V1 #843 On 26 Apr 2001, at 6:34, Hans Riesel wrote: Hi everybody, If 2^p-1 is known to be composite with no factor known, then so is 2^(2^p-1)-1. Much as I hate to nitpick a far better mathematician than myself, this is seems to be an overstatement. It is certainly true that, for composite c, 2^c-1 is composite. It does _not_ follow that no factors of 2^c-1 are known - even if c is itself a Mersenne number. There are certainly practical difficulties in finding such a factor. If c = 2^p-1 is large enough that it is known to be composite but has no known factors it's going to take some time - for example, using trial factoring, the time to test a single factor is going to be similar to the time taken to run a LL test on c. It would very likely take longer to find a factor of 2^c-1 than it would to find a factor of c. However, I suppose it's possible that someone might try, and that (with luck and perseverance) they might even succeed, for one of the smaller unfactored composite Mersenne numbers. Question (deep) - if we did discover a factor of 2^(2^727-1)-1, would that help us to find a factor of 2^727-1 ? Regards Brian Beesley 1775*2^332181+1 is prime! (10 digits) Discovered 22-Apr-2001 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 26 Apr 2001 20:07:38 +0200 From: Guillermo Ballester Valor [EMAIL PROTECTED] Subject: Re: Mersenne: More P4 timings Hi: George Woltman wrote: I just completed my first 512K FFT using the new SSE2 instructions! The 512K FFT handles exponents up to 10.3 million. Timings are as follows: 1.4GHz P4, old code:0.126 sec. 1.4GHz P4, new code:0.048 sec. 1.2GHz Athlon, 133MHz DDR: 0.084 sec. I have a few more optimizations up my sleeve. I think my goal of 0.040 seconds is achievable. I really think Intel should give you a good prize!. I can't imagine better publicity for P4. The cut of prices announced recently will help too. Good job!. Regards. Guillermo _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 26 Apr 2001 11:57:50 -0700 From: Aaron Blosser [EMAIL PROTECTED] Subject: Re: Mersenne: More P4 timings I just completed my first 512K FFT using the new SSE2 instructions! The 512K FFT handles exponents up
Mersenne Digest V1 #843
Mersenne Digest Wednesday, April 25 2001 Volume 01 : Number 843 -- Date: Sun, 22 Apr 2001 20:37:11 -0700 From: Spike Jones [EMAIL PROTECTED] Subject: Re: Mersenne: [slightly OT] Web discussion about distributed computing - --953E7B41754C35108B97B346 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Nathan Russell wrote: http://www.half-empty.org/servlet/LoadPage?pageID=ideaideaid=1644sortmode=3viewmode=3 I thought the prime community might want to stop by and take a look at what's been said. Nathan I liked your comment about the largest genuine composite: a number known to be composite but for which none of the factors are known. I suppose we could set up a computer to arbitrarily generate a few million 20 digit primes by factoring, then multiply them all together to get the largest known composite number for which none of the factors would be known, eh? spike - --953E7B41754C35108B97B346 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit !doctype html public -//w3c//dtd html 4.0 transitional//en html Nathan Russell wrote: blockquote TYPE=CITEa href=http://www.half-empty.org/servlet/LoadPage?pageID=ideaideaid=1644sortmode=3viewmode=3;http://www.half-empty.org/servlet/LoadPage?pageID=ideaamp;ideaid=1644amp;sortmode=3amp;viewmode=3/a pI thought the prime community might want to stop by and take a look at brwhat's been said./blockquote Nathan I liked your comment about the largest genuine composite: bra number known to be composite but for which none of the factors brare known.nbsp; I suppose we could set up a computer to arbitrarily brgenerate a few million 20 digit primes by factoring, then multiply brthem all together to get the largest known composite number for brwhich none of the factors would be known, eh?nbsp; spike/html - --953E7B41754C35108B97B346-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 23 Apr 2001 06:40:29 +0200 (MET DST) From: [EMAIL PROTECTED] Subject: Re: Mersenne: [slightly OT] Web discussion about distributed computing Spike Jones [EMAIL PROTECTED] comments; - --953E7B41754C35108B97B346 Nathan I liked your comment about the largest genuine composite: a number known to be composite but for which none of the factors are known. I suppose we could set up a computer to arbitrarily generate a few million 20 digit primes by factoring, then multiply them all together to get the largest known composite number for which none of the factors would be known, eh? spike Knowing that the product is composed of 20-digit primes, it can be broken by ECM. If the product has 100 million decimal digits (330 million bits), then we need 41 megabytes per residue. ECM step 1 with homogeneous coordinates needs about 6-10 such residues, so 1 Gb is more than adequate even with temporaries for FFT code. The first GCD will reveal several of the factors -- how many depends upon the step 1 limit. Perhaps one finds an 8-million-digit factor and a 92-million-digit cofactor. Both of these can be fed back into the algorithm (recursively) until the original number is completely factored. This computation can be partially parallelized. Perhaps 30 machines each get two factors, around 8 million digits and 92 million digits. Using results from two machines, we get four factors, about 64, 736, 736, 8464 digits. After incorporating results from all 30 machines, the largest factor (where all curves were unsuccessful) will be about 10^8 * (23/25)^20 ~- 8.2 million digits. Spike's idea, with 50-digit or 100-digit primes rather than 20 digits, will give hard-to-factor numbers using today's Are there any large known composite numbers c for which we know a (not necessarily prime) factor of 2^c - 1 but not of c? _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 23 Apr 2001 11:31:08 -0400 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: [slightly OT] Web discussion about distributed computing (Sprry Spike, I mistyped the list address the first time on the copy i sent to you) On Sun, 22 Apr 2001 20:37:11 -0700, Spike Jones wrote: Nathan Russell wrote: http://www.half-empty.org/servlet/LoadPage?pageID=ideaideaid=1644sortmode=3viewmode=3 I thought the prime community might want to stop by and take a look at what's been said. Nathan I liked your comment about the largest genuine composite: a number known to be composite but for which none of the factors are known
Mersenne Digest V1 #842
Mersenne Digest Sunday, April 22 2001 Volume 01 : Number 842 -- Date: Fri, 20 Apr 2001 07:38:23 - From: Brian J. Beesley [EMAIL PROTECTED] Subject: Mersenne: Minor bug in mprime v20.6 Hi, When upgrading an Athlon system from 650 MHz to 1200 MHz, I discovered a minor bug in mprime v20.6. If you try to use the Options/CPU entry on the menu to set the CPU speed above 1000 MHz, you get an error message telling you to pick a sensible value. Prime95 v20.6 is happy to accept a CPU speed of 1200 MHz; it looks as though someone forgot to relax the sanity check on the CPU speed in the mprime-specific menu code when processors faster than 1GHz started to appear. The workaround is simple. Change the CPU speed by editing local.ini, then use the menu to change the CPU type to something else then back again to generate the signal needed to inform PrimeNet about the change. I don't think we need a maintainance release at this point, but it would be nice to have the bug fixed in the next release. Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 20 Apr 2001 22:35:59 +0200 From: Martijn Kruithof [EMAIL PROTECTED] Subject: Mersenne: Mersenne stats screwed up Hello It seems like the primenet statistics got wrong one way or another, all activity since the 12th of this month has been removed from my activity report. How serious is this (only temporary / not temporary but final results checked in are ok / not ok at all checked in final results are lost) Kind regards, Martijn _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 20 Apr 2001 20:43:37 + (GMT) From: Russel Brooks [EMAIL PROTECTED] Subject: Re: [Fwd: Re: Mersenne: Distributed Computing Mandatory For Juno's Free ,Users] David L. Nicol wrote: I imagine a better GIMPS graphical display would look like part of the set from twelve monkeys with fake big black dials and twitching needles, that indicate system performance and available swap space and so forth. It could be a cute graphical system monitor application. You know, this isn't a bad idea. Over clockers already use Gimps to test their systems, why not provide some useful info too? If an OPTIONAL screen saver came with Gimps that provided useful system info we might get people attracted to Gimps to get the cool system info panel (which by the way requires Gimps to be running in the background). Cheers... Russ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 20 Apr 2001 15:55:17 -0500 From: Shane Amy Sanford [EMAIL PROTECTED] Subject: Mersenne: Primenet? Is it just me or did the Primenet database just get restored back to a April 12th version? I noticed my stats dropped back and it claims all my machines havn't checked in since April 12th (I know better).Also the exponents I've finished since that time are showing up in the Exponents Assigned column rather than the cleared section. Shane _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 20 Apr 2001 14:15:13 -0700 From: Aaron Blosser [EMAIL PROTECTED] Subject: Re: [Fwd: Re: Mersenne: Distributed Computing Mandatory For Juno's Free Users] As another point, I know many who are in SETI solely for the nice graphical display. I don't know whether GIMPS, given the abstract nature of the work we do, could ever really develop such a display. I imagine a better GIMPS graphical display would look like part of the set from twelve monkeys with fake big black dials and twitching needles, that indicate system performance and available swap space and so forth. It could be a cute graphical system monitor application. Of course you can maximize your prime95 window. Hmm... not all that interesting to most folks... perhaps just have Prime95 update some SNMP counters... I think it'd be neato to use MRTG to track various counters of the machines I have running Prime95/NTPrime. Then you're just offloading the task of doing charts and stuff to some other machine. Doesn't really address the issue of having it show some cool stuff locally, although someone could write a screen saver that takes those counters and does something
Mersenne Digest V1 #841
Mersenne DigestThursday, April 19 2001Volume 01 : Number 841 -- Date: Tue, 17 Apr 2001 19:25:45 -0400 From: vincent mooney [EMAIL PROTECTED] Subject: Mersenne: Juno Warning Someone on this list earlier warned about Juno using subscriber's computers. Here is a portion of the current Juno Virtual Supercomputer Project data. "The idea behind the Juno Virtual Supercomputer Project is simple. Today, researchers who have large, computationally demanding problems to solve often tackle them by running them on a "supercomputer," which is a computer facility that might be as powerful as several thousand separate personal computers. Juno plans to offer such researchers an even more powerful tool, by dividing such problems into a number of smaller, simpler problems, then downloading each small problem to a Juno member's computer (in much the same way that we currently download e-mail and advertisements to our members' computers) to solve. The member's computer will work on solving the small problem by running various mathematical calculations during time when the computer would otherwise be idle. These calculations will be performed only when the computer's screen saver program is running, and never when the member is using the machine. Once the problem is solved, the solution will be stored temporarily on the member's computer, then delivered to Juno during the member's next connection to our central computers (much as Juno currently stores and delivers your responses to the ads you see on the service). "I use Juno's free basic servicedo I have to participate in the Juno Virtual Supercomputer Project?" Participation in this initial phase is strictly voluntary. At some point in the future we may require some or all users of our free service to participate as a condition of using the service for free, but we expect to use volunteers to supply the computational power required for the project's initial activities. If we do make participation mandatory for free subscribers in the future, we will notify any affected subscribers by e-mail, and would expect to offer them the alternative of upgrading to one of our billable premium services if they prefer not to participate in the project. "I'm a paying subscriber to one of Juno's premium servicesdo I have to participate in the Juno Virtual Supercomputer Project?" No. Even if we decide at some point to require some or all users of our free basic service to participate in the project, we do not expect such a requirement to apply to our paying subscribers, whose participation is expected to remain strictly optional. "Should I be worried about Juno downloading data and software to my computer?" No. Juno has been downloading data and software to your computer since the day you first subscribed. Ads, for example, are already temporarily stored on your hard drive in preparation for display at times when you're not connected to Juno's central computers, just as scientific problems and data would be temporarily stored on your hard drive if you decide to participate in the Juno Virtual Supercomputer Project. Software is already downloaded for execution on your machine to allow you, for example, to respond to a promotional offer by one of our advertisers, and such responses may then be uploaded to our central computers the next time you connect to the service, in a manner analogous to the downloading of scientific problems and the uploading of results as part of the Juno Virtual Supercomputer Project. From time to time, we also download new versions of the Juno software to bring your version up to date, and we expect to download new scientific software from time to time as part of the Juno Virtual Supercomputer Project. In short, we have downloaded data and software to literally millions of people over the past five years, and have consistently done so successfully, without causing problems to our users' computers. If you decide to participate in the Juno Virtual Supercomputer Project, the main difference will be that the software and data downloaded to your computer will be used not only to support the Juno service and ad system, but also to allow your computer to perform its share of the calculations involved in various scientific problems, and to save the results of these calculations so they can be reported back to our central computers. "If I participate in the Juno Virtual Supercomputer Project, will my computer have to stay connected to the Internet all day? Will I have to be online for my computer to contribute to the project's supercomputing activities?" No. To participate in this project, your computer will only have to connect to Juno's central computers for relatively short periods of time, roughly comparable to the connections you currently make when you send or receive e-mail. The actual work
Mersenne Digest V1 #840
Mersenne DigestTuesday, April 17 2001Volume 01 : Number 840 -- Date: Sun, 15 Apr 2001 14:12:22 +0200 From: Alexander Kruppa [EMAIL PROTECTED] Subject: Mersenne: A factor of the 31st Fermat number 46931635677864055013377 divides 2^(2^31)+1 On Thursday, 12. April 2001, a factor of the 31st Fermat number (F_31) was discovered, thus proving that F_31 is composite. Since the primality proof by Crandall, Mayer Papadopoulos, which showed F_24 to be composite, F_31 was the smallest Fermat number whose primality status was unknown. That distinction now goes to F_33; a detailed list of known factors and primality status of Fermat numbers can be found at http://www.prothsearch.net/fermat. The factor was found by Alexander Kruppa on one of five AMD Thunderbird 1GHz computers located at the Technische Universitaet Muenchen. The program that was used is MFAC, written by Tony Forbes. To find a divisor of F_m, MFAC computes a list of numbers of the form (Q*k + h)*2^m + 1, where Q is 4*(2*3*5*..*q) and q is a small prime. In our case, q=11 was used. MFAC chooses h so that gcd(h*2^e + 1, Q) = 1. Composite numbers are eliminated from the list by sieving all multiples of small primes, in our case all primes = 611999. Each remaining candidate factor d is then tested by verifying the condition 2^2^n == -1 (mod d), for n = m + x, where x is the greatest integer so that 2^(x+2) | (Q*k + h). It took about 2 weeks to find the factor on the five available machines. The discoverer had checked the range up to k=10^9*2310, where k*2^33+1 is the candidate divisor, on different hardware before (as have other searchers before him) and then assigned subintervals of size 2*10^8*2310 to each machine in turn. At k=5463561471303, the factor was found. At that point, about 2.3*10^11 trial divisions with candidate divisors had been performed, while about 9*10^11 candidate divisors had been eliminated by sieving. The cofactor has 646456971 decimal digits, its primality status is unknown. We would like to thank the staff of Lehrstuhl XIII, Systemarchitektur und Betriebssysteme, an der Technischen Universitaet Muenchen, in particular Christian Rehn, for granting use of their computer hardware. Alexander Kruppa would like to dedicate the discovery to his father, Andreas Kruppa, who passed away while Alexander was making a first contact to Fermat number research by helping with the computation for the F_24 compositeness proof. Alexander Kruppa [EMAIL PROTECTED] Tony Forbes [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 16 Apr 2001 17:03:14 +0800 From: "Dave Mullen" [EMAIL PROTECTED] Subject: Mersenne: O.T. ? Factoring N with MPQS This is a multi-part message in MIME format. - --=_NextPart_000_0026_01C0C697.203242A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I've been playing around with MPQS on UBASIC, to see if I could find a = factor of M727 and/or RSA232 ... First I tried the approach of using very large factor bases ... i.e. I'd = sieve to 131071 using UBASIC's PRMDIV function, then check the remaining = residues up to about 2^48 using P-1 ... after testing 2^32 numbers, I = had a couple of full-relations, useless combinations ... When dealing with numbers of this magnitude, that kind of sieving needs = to be done on distributed-computing platforms, with hundreds of machines = taking little sections to sieve and reporting back to a main server ... = like PrimeNet etc. So then I tried a different approach of using a much smaller factor = base, and looking only for partials / double partials ... For the formula F(x) =3D a2x2 + 2abx + c, where b2 - N =3D a2c, and = checking over the range x =3D 0 to x =3D 2^32-1 ... First I look for F(n) where it is the product of small primes x one = large prime P (proved by pseudo-primality testing on a few bases), For each P, I find the two roots n1,n2 =3D=3D 0 mod P for F(x), For n1,n2, then n1+P, n2+P, n1+2P, n2+2P, n1+3P etc I checked F(m) where = it is product of small primes x P x one other large prime Q (again = proved by pseudo-primality testing), Then I scan through the resulting list looking for two results with = different n and P, and the same Q ... =20 So I end up with some Partial Relations thus f --- some small primes x P1 g --- some small primes x P2 h --- some small primes x P1 x Q j --- some small primes x P2 x Q And a bit of work ... Uf =3D a2f + b, Vf =3D a2 x some small primes x P1 Ug =3D a2g + b, Vg =3D a2 x some small primes x P2 Uh =3D a2h + b, Vh =3D a2 x some small primes x P1 x Q Uj =3D a2j + b, Vj =3D a2 x some small primes x P2 x Q Then, multi
Mersenne Digest V1 #838
Mersenne DigestTuesday, April 10 2001Volume 01 : Number 838 -- Date: Sat, 7 Apr 2001 21:51:36 +0200 (MET DST) From: [EMAIL PROTECTED] Subject: Re: Mersenne: arithmetic progression of consecutive primes From: [EMAIL PROTECTED] In a message dated 05/04/2001 05:19:38 GMT Daylight Time, "Gary Untermeyer" [EMAIL PROTECTED] writes: Let x be a prime number. Consider the series of numbers that take the following form: x, x + n, x + 2n, x + 3n, x + 4n, x + 5n, x + 6n, where n is an even positive whole number. In this series of seven numbers, can anyone tell me why, if ALL of these numbers are prime, that the minimum value of n is 210 if all the terms are _consecutive_ prime numbers? Inverting the argument, if the sequence has N terms, then n must be a multiple of all the primes = N. So in your example (N = 7), n must be a multiple of 2, 3, 5 and 7, i.e. of 210. This is still the case for N = 8 (your next case), 9, and 10. For N=11, n must be a multiple of 210*11=2310. Note that this is true for _all_ arithmetic progressions of primes, not just for progressions of _consecutive_ primes. We need the additional hypothesis that the least prime exceeds N. The primes 5, 53, 101, 149, 197 are in arithmetic progression, but the difference (48) is not divisible by 5. Likewise for 7, 157, 307, 457, 607, 757, 907. Peter Montgomery _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 10 Apr 2001 17:42:35 +0200 From: "Tobias" [EMAIL PROTECTED] Subject: Mersenne: Test This is a multi-part message in MIME format. - --=_NextPart_000_0029_01C0C1E5.A09BA3C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable This is only a test to see if it works - --=_NextPart_000_0029_01C0C1E5.A09BA3C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" HTMLHEAD META content=3D"text/html; charset=3Diso-8859-1" = http-equiv=3DContent-Type META content=3D"MSHTML 5.00.2614.3500" name=3DGENERATOR STYLE/STYLE /HEAD BODY bgColor=3D#ff DIVFONT face=3DArial size=3D2This is only a test to see if it=20 works/FONT/DIV/BODY/HTML - --=_NextPart_000_0029_01C0C1E5.A09BA3C0-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #838 **
Mersenne Digest V1 #837
Mersenne DigestSaturday, April 7 2001Volume 01 : Number 837 -- Date: Thu, 5 Apr 2001 06:38:38 +0200 (MET DST) From: [EMAIL PROTECTED] Subject: Re: Mersenne: arithmetic progression of consecutive primes From: "Gary Untermeyer" [EMAIL PROTECTED] Greetings, Although this is not a question regarding mersenne primes, I thought I'd throw this out to the readers here. Let x be a prime number. Consider the series of numbers that take the following form: x, x + n, x + 2n, x + 3n, x + 4n, x + 5n, x + 6n, where n is an even positive whole number. In this series of seven numbers, can anyone tell me why, if ALL of these numbers are prime, that the minimum value of n is 210 if all the terms are _consecutive_ prime numbers? The _consecutive_ hypothesis is not required, other than requiring x 7 and n 0. If n is not divisible by 7, then one of the seven numbers x, x + n, ..., x + 6n will be divisible by 7, hence not prime. [No two of the seven will be congruent modulo 7, so all possible remainders modulo 7 must be represented.] Likewise n must be divisible by 2, 3, 5. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 5 Apr 2001 19:33:22 +0200 From: =?iso-8859-1?Q?Torbj=F6rn_Alm?= [EMAIL PROTECTED] Subject: Re: Mersenne: arithmetic progression of consecutive primes Greetings! There are chains known today of at least 22 primes in arithmetic progression. Paul Pritchard has found a number of them. 1968 I searched for such PAP:s as they are known together with Hans Riesel, but the available computer power at that time was too hard to get. Later I picked up the old project, and I have a fairly large collection of PAP:s. Torbjörn Alm - - Original Message - From: [EMAIL PROTECTED] To: "Gary Untermeyer" [EMAIL PROTECTED]; [EMAIL PROTECTED] Sent: Thursday, April 05, 2001 6:38 AM Subject: Re: Mersenne: arithmetic progression of consecutive primes From: "Gary Untermeyer" [EMAIL PROTECTED] Greetings, Although this is not a question regarding mersenne primes, I thought I'd throw this out to the readers here. Let x be a prime number. Consider the series of numbers that take the following form: x, x + n, x + 2n, x + 3n, x + 4n, x + 5n, x + 6n, where n is an even positive whole number. In this series of seven numbers, can anyone tell me why, if ALL of these numbers are prime, that the minimum value of n is 210 if all the terms are _consecutive_ prime numbers? The _consecutive_ hypothesis is not required, other than requiring x 7 and n 0. If n is not divisible by 7, then one of the seven numbers x, x + n, ..., x + 6n will be divisible by 7, hence not prime. [No two of the seven will be congruent modulo 7, so all possible remainders modulo 7 must be represented.] Likewise n must be divisible by 2, 3, 5. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 06 Apr 2001 19:32:14 +0200 From: Henk Stokhorst [EMAIL PROTECTED] Subject: Re: Mersenne: graphical image of factoring work being done L.S., The program I wrote to track other people's work in factoring exponents in and outside the server assigned ranges has now been updated too. It is now based on the same 'core' as the program used to generate a graphical overview of all factoring work done. If you downloaded htpp://home.wxs.nl/~tha/changes_overview.zip then please upgrade to the new version, it is more flexible. Delphi source code is included. YotN, Henk. PS. Drop a note if you find the program useful, want a change or use a different method to check other peoples activities in not server assigned ranges. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 7 Apr 2001 13:15:16 EDT From: [EMAIL PROTECTED] Subject: Re: Mersenne: arithmetic progression of consecutive primes In a message dated 05/04/2001 05:19:38 GMT Daylight Time, "Gary Untermeyer" [EMAIL PROTECTED] writes: Greetings, Although this is not a question regarding mersenne primes, I thought I'd throw this out to the readers here. You will find [EMAIL PROTECTED] is also good for th
Mersenne Digest V1 #836
Mersenne DigestWednesday, April 4 2001Volume 01 : Number 836 -- Date: Mon, 02 Apr 2001 13:45:34 -0500 From: Herb Savage [EMAIL PROTECTED] Subject: Re: Mersenne: reconfigurable MP processor [EMAIL PROTECTED] wrote: This is interesting: http://www.cnn.com/2001/TECH/ptech/03/30/langley.supercomputer/index.html I wonder what the power dissipation for such a beast is? 250 watts according to their site: http://www.starbridgesystems.com/prod-hal1.html Regards, Herb Savage _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 2 Apr 2001 22:25:31 +0200 From: "Bjoern Hoffmann" [EMAIL PROTECTED] Subject: RE: Mersenne: P III 750 -E (B) Problem with "MS Me" Brian J. Beesley wrote: I have a little problem with a PIII 750 MHZ notebook, that is running prime on a 11 mio digit. It's really too slow, about a 0.4x per iteration, should be a 0.2x... Where is the problem? (1) as other people have suggested, powersaving mode. If this is the correct assumption, if you keep moving the mouse pointer (once a minute should be enough), the system will run at a "sensible" speed. powersaving is disabled, mouse moving changes nothing. (2) something else stealing CPU cycles ... ? prime95 is working on nearly 100% CPU time. (3) are these not the processors with "SpeedStep" i.e. they run at about half speed when on battery power? intel speed step is disabled. (4) many notebooks have some sort of system for manually selecting the speed from the keyboard. e.g. on a Tosh notebook, try Fn+F2. This cycles through 3 modes, "slow", "fast" "user", you can set up the powersaving CPU speed screen brightness together with the timeout values in user mode using BIOS Setup or a special utility supplied with the system. I can't find any of these settings, but I asked the manufactor of the notebook. In the end, the problem remains, the PIII750 is too slow, a 0.4x where a 0.2x should be. Interesting: CPU Benchmark with Dr. Hardware 2000 (Sofstone and Hardstone) is allright, in softstone it is faster, in hardstone a little bit slower than a Athlon 750. Maybe there is a problem with Microsofts ME (any of these drivers), which was installed on the notebook? On nearly every startup there is a ILLEGAL SUMOUT, but only on startups. There is no problem with it even after a couple of days running. Has anyone heard of problems with MS Me? Next week or so I will try Win2k or Linux. best reagrds from Germany Bjoern _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 02 Apr 2001 23:59:54 +0200 From: Henk Stokhorst [EMAIL PROTECTED] Subject: Mersenne: graphical image of factoring work being done L.S., I wrote a small program in Delphi that uses the 'nofactor' files produced by 'decomp' as input to create a graphical image of the work that has been performed on factoring. It creates a scalable image such as can be found at http://home.planet.nl/~tha/overview20010402.gif The .exe file for windows can be found at http://home.planet.nl/~tha/overview.zip it includes the Delphi 5 source files, but you can throw them away if you don't find any use for them. To monitor the changes over a period of time, say a week I wrote another program which highlights the changes made between a first and second generated file, it can be found at http://home.planet.nl/~tha/changes_overview.zip For the first program create an input file using the command 'decomp -n 0 8000' and then run overview in windows. For the second program rename the input file from 'nofactor' to 'nofactor_old', create a new nofactor file with the same range and then run factor_changes_overview. Mail me for any questions. YotN, Henk Stokhorst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 3 Apr 2001 03:59:51 +0200 From: "Hoogendoorn, Sander" [EMAIL PROTECTED] Subject: RE: Mersenne: graphical image of factoring work being done Henk Stokhorst wrote: I wrote a small program in Delphi that uses the 'nofactor' files produced by 'decomp' as input to create a graphical image of the work that has been performed on factoring. Thanks, this is something i've been looking for, much easier then importing the file into Excel (which can handle only 65536 lines) and sorting it. I found a bu
Mersenne Digest V1 #835
Mersenne Digest Monday, April 2 2001 Volume 01 : Number 835 -- Date: Fri, 30 Mar 2001 15:53:58 EST From: [EMAIL PROTECTED] Subject: Mersenne: problems with Solaris nice I run Mlucas on several Sparcs under Solaris at work, and I've noticed something not so nice about the Solaris nice command. The lowest priority Solaris allows is 19, which on any other Unix-like OS I've used would mean the job in question only gets CPU cycles if no high-priority processes are running. However, under Solaris, something run at priority 19 still tends to get a not-insignificant share of CPU time - a typical number is 15% on a system with one other full-priority job running. This has caused me to have to restrict my GIMPS work to only our least-used (read: slowest) Sparcs, since people running actual work-related jobs don't want to be slowed down by a recreational-math program. So here's my question: does anyone know of a solution to the above conundrum? The first thing that came to my mind was to run the code as a cron job, but's that's not optimal since folks here tend to run jobs at any and all hours, often overnight. What I'm thinking of is inspired by the output of the top utility - this lists (among other things) the average job load of a system, and also what % of the CPU time each active process is getting. (Since top is available for Sparc Linux, that means source code is available.) Would it be possible to write a script to basically emulate the OS's process scheduler, but which is used to control just one application? What I'd like this personal scheduler to do is the following: 1) Every few seconds get the average system load, in terms of how many CPUs would be required to run every active process at full speed; 2) If the load exceeds the available number of CPUs, suspend the user program, but keep everything in main memory; otherwise, keep running. Any such scheme, in order to be practical, would have to be executable without superuser privileges. Thanks, - -Ernst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 31 Mar 2001 08:09:52 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: problems with Solaris nice On 30 Mar 2001, at 15:53, [EMAIL PROTECTED] wrote: I run Mlucas on several Sparcs under Solaris at work, and I've noticed something not so nice about the Solaris nice command. I never did find out why the (unix) command was called "nice". My theory is that a neolithic unix hacker wanted to show off the latest tool he'd written, but couldn't think of a name for. On being shown the action of this tool, his colleague murmured "nice"! Should the Solaris "nice" command should be renamed "ugly"? The lowest priority Solaris allows is 19, I believe this is standard unix. It may be that linux et al are diverging here. which on any other Unix-like OS I've used would mean the job in question only gets CPU cycles if no high-priority processes are running. Well, that's what the documentation leads you to expect ... For reasons like making sure that interactive processes are controllable e.g. by mouse commands, there is always _some_ leakage of CPU cycles, but the proportion needn't be anything other than very small. processes are running. However, under Solaris, something run at priority 19 still tends to get a not-insignificant share of CPU time - a typical number is 15% on a system with one other full-priority job running. I sort of didn't really believe this until I checked it. But you're right! This has caused me to have to restrict my GIMPS work to only our least-used (read: slowest) Sparcs, since people running actual work-related jobs don't want to be slowed down by a recreational-math program. Sensible attitude ... doesn't bother me much on the two Solaris systems I have access to, since the other jobs running tend to be I/O bound rather than compute bound. So here's my question: does anyone know of a solution to the above conundrum? The first thing that came to my mind was to run the code as a cron job, but's that's not optimal since folks here tend to run jobs at any and all hours, often overnight. Check out the Solaris priocntl command. I think you will find that the default range of priority adjustment is 60 each way. With priocntl you should be able to fix the Mlucas process so that it adjusts much less - 10 each way should be enough. This will prevent the scheduling priority rising enough so that anyone who has another compute-bound process is losing a signficant number of CPU cycles. You may also want to use ls -ful username to see the way in which the scheduling priority, the nice v
Mersenne Digest V1 #834
Mersenne DigestThursday, March 29 2001Volume 01 : Number 834 -- Date: Tue, 27 Mar 2001 13:23:36 +0100 From: Steve [EMAIL PROTECTED] Subject: Re: Mersenne: atomic clock On Sun, Mar 25, 2001 at 10:13:40PM -0800, John R Pierce wrote: which atomic clock would that be? The US Naval Observatory master clock? http://tycho.usno.navy.mil/time.html probably has contact info. my local server time is referenced to a time server that is a few stratums removed from USNO time, my time seems to stay within about 50mS of USNO at all times. Strange that this subject should be brought up here, I noticed something in my logs a day or so ago where my machine was 4-5 minutes different from a server that I was using, can't remember weather it was mail, news or mersenne. Every time I connect to the net (probably five to six times per day), my machine synchronises its self with a time server in Manchester, North West England. So I know that my machine isn't wrong. - -- Cheers Steve email mailto:[EMAIL PROTECTED] %HAV-A-NICEDAY Error not enough coffee 0 pps. web http://www.zeropps.uklinux.net/ or http://start.at/zero-pps 1:07pm up 53 days, 13:50, 2 users, load average: 1.00, 1.00, 1.00 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 27 Mar 2001 23:09:31 -0800 From: Spike Jones [EMAIL PROTECTED] Subject: Mersenne: LL question OK I understand how you start with 4, then square and subtract 2, then take the mod M, then repeat P times. If the remainder is 0, then M is prime. But what if the mod M comes out to 1 on one of the intermediate steps? Then 1^2 - 2 = -1 Then what? spike _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 28 Mar 2001 09:41:22 +0200 From: "Hoogendoorn, Sander" [EMAIL PROTECTED] Subject: RE: Mersenne: LL question But what if the mod M comes out to 1 on one of the intermediate steps? Then 1^2 - 2 = -1 Then what? spike Then you will be stuck in a loop, same thing happens when the outcome is - -2, -1, 0 and 2 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 28 Mar 2001 10:13:22 +0200 (MET DST) From: [EMAIL PROTECTED] Subject: RE: Mersenne: LL question - - From: "Hoogendoorn, Sander" [EMAIL PROTECTED] - - But what if the mod M comes out to 1 on one of - - the intermediate steps? Then 1^2 - 2 = -1 - - Then what? spike - -Then you will be stuck in a loop, same thing happens when the outcome is - - -2, -1, 0 and 2 This case never occurs. If M = 2^p - 1 where p is prime and p 2, then M == 7 (mod 12). By quadratic reciprocity, the Jacobi symbol (3 over M) is -1, so 3 is not a square modulo M. Therefore x^2 - 2 == 1 (mod M) has no solution. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 28 Mar 2001 02:54:45 -0600 From: "Steve" [EMAIL PROTECTED] Subject: Re: Mersenne: LL question I don't believe that can ever happen, but if it did then the next step would just use mod(-1) which is p-1. The mod function never returns a negative number. Steve Harris - -Original Message- From: Spike Jones [EMAIL PROTECTED] To: [EMAIL PROTECTED] [EMAIL PROTECTED] Date: Wednesday, March 28, 2001 1:47 AM Subject: Mersenne: LL question OK I understand how you start with 4, then square and subtract 2, then take the mod M, then repeat P times. If the remainder is 0, then M is prime. But what if the mod M comes out to 1 on one of the intermediate steps? Then 1^2 - 2 = -1 Then what? spike _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 28 Mar 2001 03:26:55 -0600 From: "Steve" [EMAIL PROTECTED] Subject: Re: Mersenne: LL question Oops, I meant mod M(-1) which is M-1... Steve I don't believe that can ever happen, but if it did then the next step woul
Mersenne Digest V1 #833
Mersenne DigestTuesday, March 27 2001Volume 01 : Number 833 -- Date: Sun, 25 Mar 2001 02:08:59 -0800 From: "John R Pierce" [EMAIL PROTECTED] Subject: Re: Mersenne: Getting new GIMPSers Hmm ... my comp has NO idle time anymore (8 even with prime95 running 24/7 on my Windows2000 system, it seems to come up with a FEW idle cycles. I figure its when prime95 gets paged out or something. I rebooted a couple of hours ago after photoshop blew up and left the system kinda crispy, in the past 2h 48m, I show 3 minutes of idle time has accumulated. 2:43 has gone to prime95. the rest to everything else i've done (hardly none to a number of edit windows, web browsers, etc). - -jrp _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 25 Mar 2001 11:11:07 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: Getting new GIMPSers On 25 Mar 2001, at 2:08, John R Pierce wrote: Hmm ... my comp has NO idle time anymore (8 even with prime95 running 24/7 on my Windows2000 system, it seems to come up with a FEW idle cycles. Yes, to enable low-priority tasks to respond to events (mouse clicks etc) the scheduler makes sure every process - even the null process - gets a few cycles every so often. If you have a "normal" number of processes running you will probably have only about 99% of the actual processor cycles available to _all_ user processes. What is "normal?" Well, the task manager on my Win2K system shows 28 processes when all applications are shut. EèÛ®§ç¬ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 25 Mar 2001 10:03:01 -0500 From: Pierre Abbat [EMAIL PROTECTED] Subject: Re: Mersenne: Getting new GIMPSers On Sun, 25 Mar 2001, John R Pierce wrote: Hmm ... my comp has NO idle time anymore (8 even with prime95 running 24/7 on my Windows2000 system, it seems to come up with a FEW idle cycles. I figure its when prime95 gets paged out or something. I rebooted a couple of hours ago after photoshop blew up and left the system kinda crispy, in the past 2h 48m, I show 3 minutes of idle time has accumulated. 2:43 has gone to prime95. the rest to everything else i've done (hardly none to a number of edit windows, web browsers, etc). How does idle time accrue *to a process*? Idle time is when the CPU is not executing any process. phma _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 25 Mar 2001 19:09:02 +0200 From: "Steinar H. Gunderson" [EMAIL PROTECTED] Subject: Mersenne: Re: Getting new GIMPSers On Sun, Mar 25, 2001 at 10:03:01AM -0500, Pierre Abbat wrote: How does idle time accrue *to a process*? Idle time is when the CPU is not executing any process. Just like the brain, your computer can not `do nothing'. `Idle' time would most likely be spent in some sort of loop, possibly a HLT loop, keeping your CPU cool :-) /* Steinar */ - -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 25 Mar 2001 15:48:28 -0500 From: Jeff Woods [EMAIL PROTECTED] Subject: Re: Mersenne: Getting new GIMPSers At 10:03 AM 3/25/01 -0500, you wrote: even with prime95 running 24/7 on my Windows2000 system, it seems to come up with a FEW idle cycles. I figure its when prime95 gets paged out or How does idle time accrue *to a process*? Idle time is when the CPU is not executing any process. On a Win32 system, the idle time is kept track of by the idle PROCESS (a thread or task operating autonomously, for you *n*x types). It is by hooking into and pseudo-taking over this process that Prime95 does its work. Win32 tracks ALL processes by (I think) 32 different "priority" levels, broken into two different tiers (with only five basic priority levels from low, midium low, etc, to high).The Idle Process is but one more process running next to the Kernel, GDI, and other messaging and system processes as well as user applications. It *will* get the occasional cycle, lest it never be accessed at all, even when Prime95 is running. _ Unsubscribe list
Mersenne Digest V1 #832
Mersenne Digest Sunday, March 25 2001 Volume 01 : Number 832 -- Date: Tue, 20 Mar 2001 18:42:17 -0500 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: First illegal prime? - -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Tue, 20 Mar 2001 22:22:11 -, Brian Beesley wrote: On 20 Mar 2001, at 13:35, [EMAIL PROTECTED] wrote: (Phil Carmody's 'illegal prime') I take it "illegal" means that the particular number contains a representation in some form of language for a computer program that does something which transgresses the law. In this case, cracks DeCSS. nitpick The embedded program is a version of DeCSS, a program for cracking the CSS encryption scheme. /nitpick Slashdot takes a particular interest in this program because many of their editors and members believe that CSS is an infringment of civil rights - specifically, their right to play DVDs on the operating system of their choice. Could I point out that all computer programs and databases can be represented as simply large integers, and that, if the representation of this particular program were therefore illegal, I could claim copyright of all existing and future software for all digitally encoded systems since I can demonstrate a method of generating every possible program, video, music track, ... simply by counting? The best defence to my copyright claim might be that the expansion of pi probably contains every possible finite length sequence of digits, whatever rational base you care to use to make the expansion, and that nobody "owns" pi. Of course, (in theory) that could be seen as a disproof of all copyright - there's nothing that does not already exist. Of course, thinking of the number of possible English phrases - never mind books, or images - is a fairly easy way to come up with numbers that dwarf the Mersennes. Now I know the law's pretty darned silly, especially when it comes to deep abstract concepts like this, but really I think that it's not the integer itself which would be illegal, but its _deliberate_ use as a mechanism to crack DeCSS. _If_ cracking DeCSS is indeed illegal. Here, at least, it is, due to a particularly idiotic law known as the Digital Millenium Copyright Act, which essentially says that evading copy-protection measures is itself a crime - regardless of whether copyright is actually broken. I might note that it's impossible to encrypt something so it cannot be copied exactly; even now, it is very common for pirate DVD manufacturers to simply copy the original disc byte for byte, without even needing to crack the encryption. IMHO DeCSS is so badly broken that its proponents might as well give up now, but that's a different story. Unfortunately for them, that 40-bit encryption is now hard-coded into every DVD player; they can no more easily change it than they can suddenly start selling videotapes for the Betamax VCR. Regards Brian Beesley Nathan Russell - -BEGIN PGP SIGNATURE- Version: PGPfreeware 6.5.8 for non-commercial use http://www.pgp.com iQA/AwUBOrfq1IvPBwdDF2xqEQKDdgCeJhTSRtZD3bW+im46//1Ye7hkmCcAoL4n PFTvO4XgT1LaUfvTuSG+RBP4 =MQax - -END PGP SIGNATURE- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 20 Mar 2001 19:58:17 -0600 From: "David L. Nicol" [EMAIL PROTECTED] Subject: Re: Mersenne: First illegal prime? Nathan Russell wrote: I might note that it's impossible to encrypt something so it cannot be copied exactly; even now, it is very common for pirate DVD manufacturers to simply copy the original disc byte for byte, without even needing to crack the encryption. I guess "grey bits" never caught on. "Grey bits" were a copy-protection mechanism in which parts of the original media a program is distributed on were encoded poorly, so that repeated reads of the grey sections would produce different results. Before running, the program would try to read the grey section until something came up different. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 21 Mar 2001 12:09:44 +0100 From: "Jean Flinois" [EMAIL PROTECTED] Subject: Re: Mersenne: First illegal prime? Nathan Russell wrote: I might note that it's impossible to encrypt something so it cannot be copied exactly; even now, it is very common for pirate DVD manufacturers to simply copy the original disc byte for byte, without even needing to crack the encryption. I guess "grey bits" never caught on. "Grey b
Mersenne Digest V1 #830
Mersenne Digest Sunday, March 18 2001 Volume 01 : Number 830 -- Date: Fri, 16 Mar 2001 09:32:52 -0800 From: "Stephan T. Lavavej" [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #829 Any idea where I could get a freeware SHA checksum utility? I wrote a program to do SHA-1. It is in strictly conforming C99, except that I assume chars are 8 bits (so sue me). I have it on my webpage, http://www.its.caltech.edu/~stl/download.html . The source is extensively commented (it was my first program, so I needed to remember what I was doing). I am quite confident now that it will hash all files of arbitrary length correctly. It is GPLed, so enjoy. The commandline options it supports are pretty powerful. - -*---*--- Stephan T. Lavavej http://quote.cjb.net _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 18 Mar 2001 21:40:53 +0100 From: "Bjoern Hoffmann" [EMAIL PROTECTED] Subject: Mersenne: P III 750 -E (B) Hi *, I have a little problem with a PIII 750 MHZ notebook, that is running prime on a 11 mio digit. It's really too slow, about a 0.4x per iteration, should be a 0.2x... Where is the problem? any comments? _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------ End of Mersenne Digest V1 #830 **
Mersenne Digest V1 #829
Mersenne DigestThursday, March 15 2001Volume 01 : Number 829 -- Date: Tue, 13 Mar 2001 16:08:39 +0100 From: Guillermo Ballester Valor [EMAIL PROTECTED] Subject: Re: Mersenne: Primitive roots for Galois transforms? Hi: [EMAIL PROTECTED] wrote: Jason Stratos Papadopoulos wrote (to Peter Montgomery): Ernst Mayer and I exchanged many mailings about using GF(p^2) when p = 2^61 - 1. I thought he had implemented it, as part of a mixed integer/complex FFT. As I remember, he *had* implemented it but the project is in limbo now for several reasons: first, the Alpha compiler wouldn't interleave the integer and floating point instructions, and also Ernst mentioned that non-power-of-two transforms in GF(p^2) had some subtle difficulty (something about the order that you applied the various radices being important). Last I heard he was embarking on implementing a mixed integer/complex FFT in assembly language, but that was quite a while ago and he likely has moved on. [...snip...] The other "problem" I encountered, which you alluded to, is that one of the really nice properties of arithmetic over GF(q^2), namely that arithmetic modulo the gaussian integers closely mirrors that over the complex numbers, fails for non-power-of-2 runlengths, in the sense that the conjugation property exploited by complex FFTs which pack real inputs into half-length complex vectors no longer holds for the modular data. The conjugates are still there, but their locations in the transform output are all screwed up, to use nontechnical language. This probably can be overcome or at least mitigated to some degree, but it didn't look like it was going to be pretty when I first encountered it. But starting with a simple power-of-2 runlength implementation and using a good compiler (I plan to switch to C) should be a worthwhile effort. I wonder if there is possible to find primitive roots in GF(q^2), say a + ib, with the condition a^2 + b^2 = 1 mod q If this were possible, then (a + ib)*(a - ib) = 1 + 0i (mod q) i, e. the inverse of the root would be the conjugate, and the transformed of a real integer signal should have the same symmetries than in trigonometric complex case. Could it resolve the problem for a non-power-of-two FFT length ?. If the answer is yes: any trick to find the root other than brute force? Regards. Guillermo. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 13 Mar 2001 15:48:45 - From: "Andy Hedges" [EMAIL PROTECTED] Subject: RE: Mersenne: VB primality test program The code is a terrible mess and hardly OO. If anyone makes any radical improvements to it I would love a copy. The URL is http://www.a0a.co.uk/mirrors/mersenne/LL.zip Andy - -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Monte Westlund Sent: 13 March 2001 14:30 To: [EMAIL PROTECTED] Subject: Re: Mersenne: VB primality test program On Mon, 12 Mar 2001 22:12:54 -0800, you wrote: I'm afraid VB would be awfully slow at any sort of intensive numerical work like this, and not very good with precision either, so I rather doubt anyone has spent any signficant time on anything much more sophisticated than a erathonese sieve program -jrp I know VB would not be the first choice. It's more for benchmarking some machines(Prime95 is not an option on them), and to explore a bit. Monte _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 13 Mar 2001 07:49:48 -0800 From: Milton Brown [EMAIL PROTECTED] Subject: Re: Mersenne: VB primality test program Perhaps you could interface your VB code with Microsoft C or C++, to be faster. Milton L. Brown [EMAIL PROTECTED] Monte Westlund wrote: On Mon, 12 Mar 2001 22:12:54 -0800, you wrote: I'm afraid VB would be awfully slow at any sort of intensive numerical work like this, and not very good with precision either, so I rather doubt anyone has spent any signficant time on anything much more sophisticated than a erathonese sieve program -jrp I know VB would not be the first choice. It's more for benchmarking some machines(Prime95 is not an option on them), and to explore a bit. Monte _ Unsubscribe list info -- http:/
Mersenne Digest V1 #828
Mersenne DigestTuesday, March 13 2001Volume 01 : Number 828 -- Date: Mon, 12 Mar 2001 05:58:57 - From: "Daran" [EMAIL PROTECTED] Subject: Re: Mersenne: Security of prime95 From: Mikus Grinbergs [EMAIL PROTECTED] Newsgroups: list.mers To: [EMAIL PROTECTED] [EMAIL PROTECTED] Date: 12 March 2001 00:18 Subject: Re: Mersenne: Security of prime95 + electricity costs. I believe it is the CLIENT that initiates all GIMPS communications. In other words, there is __no__ daemon which is listening to random incoming messages. I sincerely hope not. I was a bit concerned by this in the WHATSNEW file:- #New features in Version 19.0 of mprime #-- [...] #18) The server can now broadcast important messages to the mprime client. However I think (hope) this means that it 'broadcasts' messages to clients when they connect. (Buffer overflow attacks are usually directed at programs which accept messages from anywhere on the internet.) There are two exceptions to this. 1) email and news clients can be attacked by way of hostile content in the message body or (more likely) the headers. Obviously this does not apply here, and 2) any client could be attacked by the server to which it connects. Again, the situation is a little different for a GIMPS client, from, say, a browser in that we are only connecting to a single server, which presumably, we regard as trustworthy. However, the Primenet server DOES accept messages from anywhere on the Internet, and, if cracked and owned, would be in a perfect position then to attack its clients. To make use of the GIMPS communication protocols, the attacker might have to WAIT for the user's Prime95 program to initiate contact, and would then have to SPOOF being the Primenet server. In my opinion, there are easier pickings on the 'net for attacks. That's the third scenario, and I agree that it is rare. However I don't think you can assume that an attacker is looking for easy targets. One cracking scenario is that he gains access to one machine which is connected by an intranet to other, more secure boxes. If one of them is running a GIMPS client then there's a fairly good chance that many or all of the others will be too. That would present a very tempting target. Bear in mind that, unlike a browser, a GIMPS client runs continuously, unmonitored, and often communicates when there is no human operator there. In my opinion it would be easier to spoof the "Manual Entry" Primenet server, which uses a browser interface rather than the "below-the-covers" interface of the Prime95 client. The client source code is available for anyone to inspect. [...] 2. Attacks facilitated by being on-line in the first place - I agree that the proportion of users for whom communicating with Primenet accounts solely for a significant proportion of their connection time is vanishingly small. mikus Daran G. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 12 Mar 2001 01:43:48 -0600 From: "Jeramy Ross" [EMAIL PROTECTED] Subject: Re: Mersenne: prime95 - v21 progress Brian J. Beesley wrote: I fail to see how reducing the check-in interval would have any impact on the "problem". Those people who are checking in every 28 days aren't running into the 60-day expiry deadline. For one, the reduced check in time would allow the closer watch of "suspect" users who download a exp., run the program for a few days and then ditch out on the project. While it is true that people may run the program for upwards of a month or so and then ditch. The idea of having them check in about every week AS A DEFAULT too keep tabs on them while they have their FIRST exp. would aid in finding someone who ditches out. The process in which we use this aid is up in the air. The 60 day expiry value is a server parameter, not a client parameter. In any case, as I explained above, I think that a drastic reduction in the value would be dangerous. I think it is realized that the 60 day value is a server parameter, and the change in value would be only effective for FIRST TIME users. Besides, I don't know of many users who have a problem checking in every week to keep things moving smoothly. Best wishes, Jeramy _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 12 Mar 2001 12:53:15 +0100 From: Alexander Kruppa [EMAIL PROTECTED] Subject: Re: Mersenne: Security of prime95 Com
Mersenne Digest V1 #826
Mersenne Digest Sunday, March 11 2001 Volume 01 : Number 826 -- Date: Sat, 10 Mar 2001 12:08:09 +0100 From: "Robert van der Peijl" [EMAIL PROTECTED] Subject: Re: Mersenne: numbering the messages Steve ( [EMAIL PROTECTED] ) wrote on Saturday, March 10, 2001 at 02:24:00 + X-Mersenne-Count 229 X-headers, good idea. I agree, no need to reset the message count. But having said all of that I don't really think there's much point in doing this. We can't all share the same opinion :-) But I'll ask you this: how many Mersenne list messages have you missed since you joined the list? Respectfully, you probably don't know. Would you want to miss, say, a posting by George Woltman, and not know about it? It's common practice in the printed world to consecutively number the publications. Besides, I don't think it's that difficult to add a message counter. (Could you give me a good reason why the server shouldn't number the messages?) As Joshua Zelinsky put it: automatic numbering would be pretty helpful. Maybe Luke Welsh would give his opinion on this subject? Happy hunting, Robert van der Peijl - -- Your mouse has moved. Windows NT must be restarted for the change to take effect. Reboot now? [ OK ] [ YES ] [ APPLY ] - -- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 10 Mar 2001 15:26:08 + From: Steve [EMAIL PROTECTED] Subject: Re: Mersenne: numbering the messages On Sat, Mar 10, 2001 at 12:08:09PM +0100, Robert van der Peijl wrote: We can't all share the same opinion :-) But I'll ask you this: how many Mersenne list messages have you missed since you joined the list? Don't know. Respectfully, you probably don't know. Would you want to miss, say, a posting by George Woltman, and not know about it? Missed many before I joined the list and the world kept on turning. It's common practice in the printed world to consecutively number the publications. Besides, I don't think it's that difficult to add a message counter. (Could you give me a good reason why the server shouldn't number the messages?) Well there isn't a good reason why not, and there is already a counter of sorts in the Message ID in the header, but it's not very human readable. Surely the list management software keeps a count of how many posts have been sent out to the group, it's just a case of reading/writing that digit into a header line. - -- Cheers Steve email mailto:[EMAIL PROTECTED] %HAV-A-NICEDAY Error not enough coffee 0 pps. web http://www.zeropps.uklinux.net/ or http://start.at/zero-pps 3:10pm up 36 days, 16:51, 2 users, load average: 1.16, 1.14, 1.06 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 10 Mar 2001 10:15:15 -0800 From: "John R Pierce" [EMAIL PROTECTED] Subject: Re: Mersenne: numbering the messages Well there isn't a good reason why not, and there is already a counter of sorts in the Message ID in the header, but it's not very human readable. Surely the list management software keeps a count of how many posts have been sent out to the group, it's just a case of reading/writing that digit into a header line. digests are generally numbered, while regular postings are passed thru the email list server systems relatively unscathed (other than appending the tag at the bottom). Majordomo at least doesn't keep any sort of counters. I guess it could be modified to do so, but this could get messy on a large busy server (afaik, multiple messages can be in the queue at once getting handled by parallel processes, so updating this counter would have to be done on an 'atomic' basis... preventing deadlock issues etc complicates matters) - -jrp _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 10 Mar 2001 19:56:59 +0100 From: Martijn [EMAIL PROTECTED] Subject: Re: Mersenne: prime95 - v21 progress This message apperently got lost, so I sent it again (so sorry if you receive it twice / how appropiate the number though discussion) Hello, when looking at the data it can clearly be seen that computer speed is not the problem for progress currently, expiring exponents are. (Why are checks started on those exponents anyway nowadays, the 3xx
Mersenne Digest V1 #827
Mersenne Digest Sunday, March 11 2001 Volume 01 : Number 827 -- Date: Sun, 11 Mar 2001 17:21:25 -0500 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: Ways to increase recruitment. On Sun, 11 Mar 2001 12:03:47 -0500, Joshua Zelinsky wrote: The vast majority of computers still aren't doing any form of distributed computing. Here are a few suggestions to help increase GIMPS participation: 1. Get people at major universities + colleges to become "active recruiters," posting messages on announcement boards, talking to friends and faculty. We should all be doing this sort of stuff anyways, but if we could get people to volunteer/coordinate efforts, we might get a lot out of it. I've always discussed GIMPs with my friends, in and out of college. I think the problem is that it's harder to understand what GIMPS actually does than it is with, e.g., seti@home. 2. Give people/teams some form of credit for recruiting people. This could be done as competition separate from the main one, or somehow connected. We could probably have people list an option of listing a "sponsor" or "sponsors" already on GIMPS when they join. Competition almost always makes things work better. GIMPS has never worked that way, nor has any (not-for-profit) distributed computing project of which I am aware. In fact, the only programs I am aware of that /do/ work that way are for-profit distributed computing efforts like processtree, and earn-for-surfing programs. 3. Post periodic announcements to sci.math and other discussion groups. In particular, if someone asks a question about Mersenne primes someone should answer it and throw GIMPS in as well. I'm alrwady doing this, but I can't get every group. If we organize to split them up, assigning different groups to different people, it might help out a lot. That's an interesting idea - the only concern is making sure the 'periodic announcements' aren't resented by the users of said groups. Sincerely, Joshua Zelinsky [EMAIL PROTECTED] Nathan _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 11 Mar 2001 23:32:03 +0100 From: "Martijn Kruithof" [EMAIL PROTECTED] Subject: RE: Mersenne: Security of prime95 + electricity costs. I have verified the possibility of a buffer overflow exploit in primenet.c (used in linuxs mprime) It seems NOT vurneralbe (so it seems safe to me) NO buffer overflow is likely to occur. Notwithstanding I am running mprime as user mersenne with virtually no rights and no shell. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 12 Mar 2001 00:20:12 +0100 From: Alexander Kruppa [EMAIL PROTECTED] Subject: Re: Mersenne: prime95 - v21 progress "Brian J. Beesley" wrote: (1) Removing these assignments from PrimeNet and managing them seperately. Anyone who is prepared to make special arrangements to acquire these assignments is unlikely to default by reason of lack of commitment. Someone is (or was?) doing something similar - David Campeau (sp?), aka diamonddave, who set up scripts to grab small exponents right after the Primenet servers recycle run and completed them in ascending order of size. And boy, did he get flamed for it. Right, flamed - because some only looked at the 20 or so small exponents he had reserved and tought he was holding them back. Maybe those who complain about slow "linear" progress could take on a similar approach? (except for the getting flamed part, I hope.) Write a script that (or get up early/stay up late to) get exponents right after the servers recycle run and immediately release the biggest ones so you have enough work for, say, 30 days. Maybe David can help with the scripts or general tips for maintaining the exponents list, *especially* safe guards so that reserved exponents dont pile up in an uncontrolled manner. If everyone sticks to the rules - don´t poach, dont hog exponents - this should solve most of the problem with the least possible hassle. Those who want to see milestones soon can help to get there, the rest can just go on with their regularly assigned work. This doesn´t help with the exponents that are currently reserved with a expected run time of several years - but if the user abandons them, the server will recycle them 60 days after the last update from the user which doesn´t seem like an overly long delay for the project. If the users chooses to complete the exponent on a slow machine or on a machine that is not in use very often, then I don´t se
Mersenne Digest V1 #825
Mersenne DigestSaturday, March 10 2001Volume 01 : Number 825 -- Date: Fri, 09 Mar 2001 07:34:23 +0100 From: Martijn [EMAIL PROTECTED] Subject: Re: Mersenne: prime95 - v21 progress Henk Stokhorst wrote: L.S., Maybe it would be a good idea to have a special version of prime95 that has an option to request exponents that have expired after having been reserved for a long time without any progress being on the work for that exponent. The server should issue those exponents only to people who have that option. That version should only be available to people who have fast (700 MHz or more) machines running most of the day. That would help prevent exponents expiring multiple times. YotN, Henk Stokhorst Nope bad idea smaller exponent = smaller runtime = lower clock frequency so it would then be better to have them assigned to machines that are slow real pentiums for instance (It does really not matter if such an exponent is finished in 4 or 30 days. The multple expiering problem is an entirely fake one. It does not hinder progress, it only makes (relatively small) exponents unavailable for 90 days, in that time we work on other exponents and life goes on. Martijn Kruithof _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 9 Mar 2001 08:29:35 +0100 From: "Robert van der Peijl" [EMAIL PROTECTED] Subject: Mersenne: expired exponents We might not need a special version of prime95. How about if the _PrimeNet server_ itself only issue expired exponents to "power"-users? If that is a real possibility, perhaps Scott Kurowski could look into that? Robert. - - Original Message - From: "Henk Stokhorst" [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Friday, March 09, 2001 12:45 AM Subject: Re: Mersenne: prime95 - v21 progress L.S., Maybe it would be a good idea to have a special version of prime95 that has an option to request exponents that have expired after having been reserved for a long time without any progress being on the work for that exponent. The server should issue those exponents only to people who have that option. That version should only be available to people who have fast (700 MHz or more) machines running most of the day. That would help prevent exponents expiring multiple times. YotN, Henk Stokhorst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 9 Mar 2001 02:24:15 -0800 From: Scott Kurowski [EMAIL PROTECTED] Subject: Mersenne: RE: expired exponents Hi Robert, [Robert van der Peijl:] We might not need a special version of prime95. How about if the _PrimeNet server_ itself only issue expired exponents to "power"-users? If that is a real possibility, perhaps Scott Kurowski could look into that? I would instead recommend a broader strategy that expires exponents based upon the assignment age (days run) and current iteration at null (not started), perhaps at 60 days age. Did someone already suggest that? This will have the system effect of generally causing machines that grab and hold excess exponents to lose smaller exponents to new or more productive machines, while making up for those losses by grabbing fewer, ever larger exponents. This would happen in addition to the current automatic expiration process. The risk that a machine actually started a long-held exponent before contacting the server to learn it had been reassigned is somewhat greater. The result would be slightly more frequent 'opportunistic' double-check passes as the machine forges along to complete the then-redundant test, probably after the reassignment machine finishes. Maybe that's a good thing. George Woltman manages the server's individual exponent and range assignments from time to time. If overriding a 'squatter' is important enough, he could do so manually. However, if server changes are necessary, we defer to him for those requirements. (If there are replies, please cc me directly since I receive only the Mersenne list digests.) regards, scott kurowski Entropia, Inc. San Diego, California P.S. if there are any GIMPS folks on this list nearby, I'll treat lunch or beers... I left Ernst and Luke in Silicon Valley. :-( _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 9 Mar 2001 11:09:53 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersen
Mersenne Digest V1 #824
Mersenne DigestThursday, March 8 2001Volume 01 : Number 824 -- Date: Tue, 06 Mar 2001 17:08:37 -0500 From: "Joshua Zelinsky" [EMAIL PROTECTED] Subject: [none] The list has been pretty quiet lately... This is a little embarrassing but I was thinking of switching my iterations between screen outputs to 1 for Prime95, just to make it "feel faster." However, I wasn't sure how much resources it would take up. I checked and it seems negligible. Is that true? Are there any other reasons to set the number that low? Regards, Joshua Zelinsky [EMAIL PROTECTED] _ Get your FREE download of MSN Explorer at http://explorer.msn.com _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 6 Mar 2001 23:40:24 +0100 From: "Steinar H. Gunderson" [EMAIL PROTECTED] Subject: Mersenne: Spontaneous Reboots, The Final Message (TM) Just to finish off what seemed to create the longest thread for quite a while on this list: My machine came back today, with a replacement motherboard of exactly the same type. It now works flawlessly, or at least it has run mprime for 6-8 hours now with no problem at all (the old one had a bit habit of rebooting _while in the BIOS_ for its last hours)... So... is it now a new machine? How much do you change before you can call it a new machine? ;-) /* Steinar */ - -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 6 Mar 2001 23:50:15 +0100 From: "Shot" [EMAIL PROTECTED] Subject: Mersenne: PII 233 vs Cel 333 Hello. I just checked the benchmarks on http://mersenne.org/bench.htm - is Pentium II 233 MHz really that much slower than Celeron 333 MHz (79 days vs 58 days for the default 1100 exponent)? I ask because I just put together my uncle's Duron 650 and as a gratitude I got his old Pentium II 233 (+ motherboard). I guess it's not worth selling, so I'm thinking about putting a second computer (next to my Celeron 333) and I wanted to know which one is faster (or how much speed is architecture- and how much clock-dependand). Cheers, - -- Shot - --- http://shot.prv.pl/ GCS/CC/IT/O d- s:+: a--? C++(+++) ULS P+ L(+) W++$ N++ w(--) PS+(++) PGP- t 5 X- R tv- b+ DI D G++ e* h- r+ y+** - - Geek Code Decoder: http://www.ebb.org/ungeek/ God created the world out of nothing, but the nothingness still shows through. - -- Soren Aabye Kierkegaard _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 7 Mar 2001 03:11:22 +0100 From: "Robert van der Peijl" [EMAIL PROTECTED] Subject: Mersenne: prime95 - v21 progress Joshua Zelinsky wrote on Tuesday, March 06, 2001 at 17:08:37 -0500 : The list has been pretty quiet lately... Could it be that's because everyone is holding their breath for prime95 v21? But that might still take quite a while, since AFAIK no public announcement has been made about its scheduled completion date. Of course, that date would depend on the intended new features. Still, some indication would useful -- say, between 3 and 9 months from now?? Personally, it would help me in deciding whether to continue translating the v20 readme file into my language (Dutch), or to wait for the new stuff. Hey, how about calling it primeXP? It would allow the new user to run only 50 iterations, after which time registration is mandatory. We would have to uglify (is that good English?) the user interface however, to make the whole thing believable. And, existing software should no longer be able to execute with our new version. Those two criteria may be quite hard for us to fulfill. What software company could we ask to implement those changes for us? The Good Thing (TM) would be, that no new features would be necessary. But then we'd have to charge a lot of money for the product. The revenues could go to Bill Gates' family -- to help them extend their house. This is a little embarrassing but ... That's quite allright, this is a private conversation, right? :-) I was thinking of switching my iterations between screen outputs to 1 for Prime95, just to make it "feel faster." Actually, I have several alternative suggestions to make it, how did you put it, 'feel faster'? Do something
Mersenne Digest V1 #822
Mersenne DigestSaturday, March 3 2001Volume 01 : Number 822 -- Date: Tue, 27 Feb 2001 19:55:15 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: CPU operating temps On 27 Feb 2001, at 8:56, Brian Last-Name wrote: I am running a Cyrix 233 OC'ed to ~266 by a faster bus speed. I cannot touch the processor heat sink for more than two or three seconds without pain, and the voltage regulators are even hotter. It has been running trial testing for over two years without many "issues". Older designs are more resistant to overheating because there is a lower probability of electrons released by excess temperature from making their way through to an adjoining circuit. The circuits are in much closer proximity with modern high-density designs. People's tolerance to heat pain does vary; because of thermal conductivity, handling hot metal isn't easy, most people will begin to register pain at ~50C (120F). At ~70C (156F) few people will be able to hold hot metal for more than a second. A few degrees above that and touching for more than a split second will cause obvious burns. Casting my mind back a few years, I seem to remember that Cyrix processors were noted for hot running. Voltage regs running hot are fine. They're not subject to data corruption caused by overheating. Either they work, or they cook themselves to death. I havent even been using frag tape or heat conducting grease. These are more neccessary with newer designs, because their heat ouput per unit area is much greater than with old designs, and it's therefore more neccessary to conduct excess heat away from the chip efficiently. What is the maximum operating temperature (recommended) for a processor? I will measure the temp. at the bottom of the heat sink while operating. Technically you're looking at around 130C at the hottest point inside the circuitry of the working chip. There's _no way_ to measure that, without more access to the chip than a working processor usually has available, and even then without specialist equipment like a pyrometer. The position of the temp sensor depends on the processor cartridge and/or motherboard design. Slotted Intel PII/PIII have the thermistor mounted on the small board inside the cartridge; slotted Athlons don't come with a thermistor, if you want that option you have to mount one yourself, the only place to do it is to wedge the thermistor between the fins of the heatsink. Socketed designs usually have the thermistor mounted in the "hole" in the CPU socket, immediately under the processor itself. Obviously these different mounting methods will all read "low" compared with the critical temperature internal to the chip, but how low depends on many factors. Therefore it isn't possible to give a maximum temperature without knowing several other variables. If your system has been running for two years, still passes the Prime95/mprime self test isn't either crashing frequently or producing error messages frequently when Prime95/mprime is running, it's not actually overheating. Don't worry about it. Start worrying if and only if you start seeing symptoms which could possibly be attributed to overheating. My standard procedure is, some time around July when the weather is warm, to remove all the "SelfTest" lines from local.ini. Prime95/mprime will then re-run the self-test next time it needs to use each FFT run length. If overheating is going to hit you, it's _much_ more likely to be a problem when the system is operated in an unusually warm environment. Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 27 Feb 2001 14:55:25 -0600 From: "Jeramy Ross" [EMAIL PROTECTED] Subject: Re: Mersenne: CPU operating temps First, it is quite normal for a processor to run hot enough to prevent one from being able to touch it for over 2 secs or so. When Intel first introduced the PII, a common joke in computer science circles was that Intel had successfully marketed the most expensive egg frier to date ;-) To find the specific temp info you need to go to http://www.cyrix.com and look up your processor. Alot of manufacturers produce several versions of a specific processor that have different heat tolerances. I know that AMD K6-2's had a copule different versions per clock speed (atleast at 500MHz) that had about a 10 degree C difference in their tolerance. If I remember right, the average safe (or sometimes called normal) max. is arround 70C which is arround 158F, BUT this varies alot! Secondly, One *should* use some sort of thermally conductively compound b
Mersenne Digest V1 #821
Mersenne Digest Tuesday, February 27 2001 Volume 01 : Number 821 -- Date: Fri, 23 Feb 2001 22:33:09 + From: Gareth Randall [EMAIL PROTECTED] Subject: Re: Mersenne: Spontaneous reboots CPU overheating? Have you opened the case, and checked the condition of the CPU fan? It sounds as if the CPU is overheating once the FPU warms up. Is your heatsink sufficient? Is it full of dust? Open it up while the machine is running and check that the fan really is spinning, and at a decent speed. "Steinar H. Gunderson" wrote: After being away for five days recently, I noticed that my computer (running Linux kernel 2.4.1, by the way -- 2.4.2 now) had rebooted. Just a few hours later, it rebooted again -- and that night, it rebooted _again_. If I turn off mprime (v20), the problem goes away -- the computer doesn't reboot, at least not the 36 hours I tested. After I start mprime, it reboots in just a couple of minutes now. Yours, === Gareth Randall === _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 23 Feb 2001 14:48:25 -0800 From: "Michael LeBlanc" [EMAIL PROTECTED] Subject: Re: Mersenne: Spontaneous reboots If I turn off mprime (v20), the problem goes away -- the computer doesn't reboot, at least not the 36 hours I tested. After I start mprime, it reboots in just a couple of minutes now. mprime doesn't run as root, the machine has run mprime stably since I got it (about a year) and the machine (an Athlon 800, running on an Abit KA7-100 mainboard) is not overclocked. Does anybody know what's going on here? Like I said, it's been going fine on the same exponent for quite a while now, but suddenly, it just feels like rebooting (no error message or anything, the screen just goes blank and suddenly it's in the BIOS). The voltage meters in the BIOS screen look OK, and there should be more than enough power for the PC... Strange... Any ideas? I also had a KA7 with an athlon 750. I had the exact same problem as you seem to have. For me, it only rebooted while running video editing software (on windows). The problem got worse and worse until it just died a couple of days ago. I took out the motherboard and noticed that some of the electrical components (the ones right in front of the processor) were all scorched and leaking some black residue. I think those components are the voltage regulator for the processor. Right before it died completely, it would only last a few seconds after being turned on. I turned it on and went into the bios's "PC-health" section just in time to see the processor voltage drop steadily to about 1.6v. Then the screen went blank. It might not be the same problem you are having, but it sounds similar. You might want to check those capacitors (i think...) in front of the processor. Maybe they are overheating? Or, I've heard that KA7's had a voltage issue with some graphics cards. Maybe it's related... Either way, I've ordered a SOYO board for a replacement. Michael LeBlanc _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 23 Feb 2001 23:59:56 +0100 From: "Steinar H. Gunderson" [EMAIL PROTECTED] Subject: Mersenne: Re: Spontaneous reboots On Fri, Feb 23, 2001 at 10:33:09PM +, Gareth Randall wrote: CPU overheating? Hmm... The BIOS says the system temperature is at 25 degrees Celsius -- not exactly much, is it? Haven't got anything to measure the _CPU_ temperature, though... Have you opened the case, and checked the condition of the CPU fan? It sounds as if the CPU is overheating once the FPU warms up. Is your heatsink sufficient? Is it full of dust? Open it up while the machine is running and check that the fan really is spinning, and at a decent speed. Actually my cover is off all the time -- the fan is spinning, and not full of dust (although there _is_ dust other places in the case). The BIOS says it's spinning at 4500 RPM -- not a bad number either. I might try to clean out some of the dust -- could that help? /* Steinar */ - -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 23 Feb 2001 18:02:32 -0500 From: "Paul Victor Novarese" [EMAIL PROTECTED] Subject: Re: Mersenne: Spontaneous reboots After being away for five days recently, I noticed that my computer (runnin
Mersenne Digest V1 #820
Mersenne Digest Friday, February 23 2001 Volume 01 : Number 820 -- Date: Tue, 20 Feb 2001 11:26:28 +0100 From: "Siegmar Szlavik" [EMAIL PROTECTED] Subject: Re: Mersenne: Accuracy of completion dates. On Mon, 19 Feb 2001 23:02:46 -0500, Jeff Woods wrote: Suggestion: the next version of Prime95 should contact the server after every 10% of an LL test. Based on how long this took, the server would calculate the probable finishing time. This estimate would probably be more accurate than the rough estimate based on how many hours the computer is estimated to be on which ignores for what the computer is normally used. The only drawback I see is the strain on the server. It can already be CONFIGURED to do so, not on percentages, but on number of days between contacts. I have mine set to report daily, so my individual report is always up to date. Same here... unfortunately ntprime doesn't report to the server if it is in the 'sleeping mode'. I would find it usefull if it would do so, or at least on startup - just to say: 'hey, I didn't do any new calculations, but I'm still here'... for all the office-machines which are configured to run only over night and on weekends, but are normally turned off. Siegmar _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 20 Feb 2001 22:17:53 +0100 From: "tom ehlert" [EMAIL PROTECTED] Subject: Mersenne: Mersenne exponent assignement strategie I personally don't mind a P100 running full LL tests; they are a small, but usefull contribution to our effort. My own dual P700 makes a somewhat larger, but still small contribution to the project, compared to some other 3+ maschines out there. the point was, is and should remain: every single cycle is useful. BUT I think, many people (oncluding me) want to see more Milestones finisheshed earlier. While the server is currently giving out assignment in the 12.3xx.xxx range, we haven't yet finished 5.558.701. looking at the status, I would consider LL up to 10.000.000 : 95% done DC 4.500.000 : 95% done, both with a very long tail. I think, the reason for this is NOT some very slow 486's running dull screensavers, but exponents, which have been recycled several times. here's my proposal: on the server side, set a limit (currently for LL=11.000.000, DC=5.000.000) define a RPTM= 'reasonable performing, trusted maschine' as a maschine, which has at least returned 2 results (scince last syncronization?) then: if a maschine asks for new work: if its 'reliable and reasonable fast' (has returned two results) give it the smallest exponent available else give it some expomnent above limit. this would: all overclockers - time out, before they hold the overall progress favor faster maschines at the tail - they could probably increase the DC milestone to 10.000.000 whithin a moth, if allowed to significantly narrow the gap between the frontrunners (12.3xx.xxx) at the backrunners (~5.300.000) REPEAT: I don't mind a P100 helping in our project; even a P100, runnining 8 hours a day, will finish M1200 within 2 years, 8 days; I will happily wait for it; the gap between our 12.xx and 5.xx is larger as the surrent progress (on the front) is roughly 2.500.000/year. Happy cycling to everybody tom ehlert _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 21 Feb 2001 09:02:12 +0100 From: "Hoogendoorn, Sander" [EMAIL PROTECTED] Subject: Mersenne: Hybernation I personally don't mind a P100 running full LL tests; they are a small, but usefull contribution to our effort. I still use an old p100 and p166 to do a full LL test in the 9M range, but i do check in regularly and make sure that i won't hold up a new milestone. But i got another question, does anybody have experiance with prime95 and hybernation? Does the program pickup where it left correctly? Sander _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 21 Feb 2001 11:24:34 +0100 From: "Lukasz Slachciak" [EMAIL PROTECTED] Subject: Re: Mersenne: Hybernation But i got another question, does anybody have experiance with prime95 and hybernation? Does the program pickup where it left correctly? Sander After your question I've checked it on my Windows 2000 (on Duron 700, Motherboard AK33). It works correctly
Mersenne Digest V1 #818
Mersenne Digest Saturday, February 17 2001 Volume 01 : Number 818 -- Date: Thu, 15 Feb 2001 18:31:24 + From: Steve [EMAIL PROTECTED] Subject: Re: Mersenne: PrimeStats, Perl script for the PrimeNet Top Producers Table My apologies and thanks to Andy for pointing out that one of the files was corrupted in the tarfile. I've fixed it now. - -- Cheers Steve email mailto:[EMAIL PROTECTED] %HAV-A-NICEDAY Error not enough coffee 0 pps. web http://www.zeropps.uklinux.net/ or http://start.at/zero-pps 6:29pm up 13 days, 20:08, 2 users, load average: 1.06, 1.06, 1.05 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 15 Feb 2001 23:16:35 +0100 From: "Dieter Schmitt" [EMAIL PROTECTED] Subject: Re: Mersenne: PrimeStats, Perl script for the PrimeNet Top Producers Table Hi Steve, lets do more chasing ;-) Because its a very long time ago I had a look on program codes I'm not sure to understand all of this stuff. But I think you are using the P-90 h/day values without changing them, don't you? I think the actual performance values are to be computed again to be useful, because there are many people upgrading and therefore ranked high but showing lower performance values at P-90 h/day as other participants ranked nearby. i.e. today I'm ranked at 445 with 22.882 years/148 exponents(IPS)/182,22 P-90 h/day Currently I'm running Prime95 on three machines (2 GHz total) equal to 22,0 P-90 CPUs. This means 528 P-90 h/day but completing one LL-test at 12M range only adds less than five P-90 h/day. There's a difference between 182 P-90 h/day at top producers list and 528 P-90 h/day (actual performance). How to calculate the actual performance of an upgraded account of user X? To do this I'm calculating the average P-90 h/day of such participants near the rank of user X having higher values than X. The other users near X with lower values did some upgrading recently too and therefore are to be neglected. Computing the average out of 10 such values in front and 10 such values behind the rank of user X works well. I called it the local average. Using 20 such values nearby my own ranked ID (dismit) gives the local average of 310 P-90 h/day. Of course, this isn't a very good approximation. But the 182 P-90 h/day on the list means 58.7% of the local average of 310 P-90 h/day. Thus divide the local average of 310 by 0,587 and use the result which is very near to the already known performance of 528 P-90 h/day. Does anybody know a pretty formula of this algorithm? Why does it work at all? Have fun Dieter Schmitt - -Ursprüngliche Nachricht- Von: "Steve" [EMAIL PROTECTED] An: [EMAIL PROTECTED] Gesendet: Donnerstag, 15. Februar 2001 16:56 Betreff: Mersenne: PrimeStats, Perl script for the PrimeNet Top Producers Table Hi Primepickers PrimeStats is a perl script that interogates the top producers table at: http://mersenne.org/ips/topproducers.shtml, after you've saved it to disk, it will give you a report on participants as specified by yourself in a seperate data file. The script will also give you a detailed report of the future prospects of one user ID that you supply to the script via the command line, this detailed report tells you how many people are in front of the user but going slower and how many people behind but going faster and gives you estimates of when the user will catch the pack in front and when the chasing pack will catch up etc. The script is available here: http://www.zeropps.uklinux.net/linstuff.html And here is a sample report that finds current details for 10 users and gives a detailed report for one of them (me): Run Date: Thu 15 Feb 2001 Participants counted: 20,018 Extra details for user ID: sjlen Position User Name CPU YearsExponentsCPU P90 Tested Hrs Per Day 1264 S18743 8.921 16225.16 3056 felipel 3.667 8 49.83 3171 sjlen3.512 7 66.59 3496 mbandsmer3.050 19 24.85 4021 Pse 2.488 5 45.91 5394 Lalo11.549 18 12.62 5981 S16318 1.319 3 28.17 6773 mage21 1.010 3 17.49 7411 S17376 0.838 2 19.11 7434 Paradoks 0.833 7 6.84 3171 sjlen3.512 7 66.59 712 people are faster than you but behind you, at an average speed of 115.
Mersenne Digest V1 #817
Mersenne Digest Thursday, February 15 2001 Volume 01 : Number 817 -- Date: Tue, 13 Feb 2001 09:44:56 -0500 From: Jud McCranie [EMAIL PROTECTED] Subject: Re: Mersenne: Processor short family histories At 12:54 AM 2/13/2001 -0600, Ken Kriesel wrote: Intel offered the 286 with 6, 8, 10, and 12.5 Mhz on one data sheet. AMD got to 16 on this one, but an early data sheet lists 4, 6, and 8 (and says reprinted by permission of Intel). FPU was separate. I don't recall a 286-20. Dell had one. At the time I got my Dell 20 MHz 386 (fall 1987) they had a 20 MHz 286. The 386 debuted at 12.5 and 16 Mhz. I thought it debuted at 16. I never heard of a 12.5 MHz 386. ++ | Jud McCranie | || | 137*2^261147+1 is prime! (78,616 digits, 5/2/00) | ++ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 13 Feb 2001 17:20:43 +0100 From: Henk Stokhorst [EMAIL PROTECTED] Subject: Re: Mersenne: Processor short family histories Jud McCranie wrote: At the time I got my Dell 20 MHz 386 (fall 1987) they had a 20 MHz 286. ;-) If it is time to brag about our computers, I owned (still have it) a DAI homecomputer back in 1978 with a 8080A processor running at 2 MHz. And it was blazingly fast. YotN, Henk Stokhorst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 13 Feb 2001 18:16:18 +-100 From: Denis Cazor [EMAIL PROTECTED] Subject: RE: Mersenne: P4 speed and implications thereof John R Pierce wrote the P4 is likely gonna ramp up to 2GHz, 3Ghz and beyond faster and farther than AMD can ramp up the Tbird. The problem with Intel, is they have difficulties to sustain AMD performance, so they wanted to announce higher frequencies, to be the first again. So they doubled the number of pipeline stage from 10 to 20 and they obtained a P4 - 1.4 GHz having the same performances a P3 - 700 MHz. The gain is only on "vectorized" data, when the pipe is full, as on graphics treatments. Jud McCranie wrote Yes, most Intel chips max out at about 2.5 times their initial speed, and they expect the P4 clock speed to go up by at least a factor of 10. And they claimed 1.4 GHz and perhaps 10 GHz soon,to make dreaming on P4. Tomorrow is another day Their objectif is only publicity. G4 with small number of pipe line stage has small frequencies but quite the same performances. On the way, 64 bits machines, with Thunderbird like, micro-decoded and 8086-compatible, very performant and inexpensive. Intel product, 8086-incompatible ... Best regards, Denis Cazor, Paris _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 13 Feb 2001 10:09:13 -0800 (PST) From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: P4 speed and implications thereof On the way, 64 bits machines, with Thunderbird like, micro-decoded and 8086-compatible, very performant and inexpensive. Intel product, 8086-incompatible ... the 86 architecture is a dinosaur, designed in 1978 to inherit features of the 8080 which was designed in 1973, and needs to die. IA64's VLIW architecture is far more modern, and will carry performance to a far higher level than 64 bit extensions of the same old EAX, [EBX*4+ESI].offset stuff. Anyways, the IA64 has a full pentium compatibility mode, and supports mixed mode processing where you can have 64 bit code running under an extended 32 bit OS, and visa versa, so I dunno what this 'incompatible' noise is about. as far as G4 goes, what I've read and heard is that the performance doing regular programming is fairly poor, its only specific "SIMD" benchmarks that achieve the high numbers Apple likes to toss around. Anyways, to achieve really high clock rates on a complex instruction set you HAVE to go to a deep pipeline. RISC processors got away with a simpler pipeline entirely due to the simplicity of their instruction sets, and even they have run into clock speed limitations that are not easily overcome... All the current high end risc engines have had to resort to things like super-scalar architecture and incredibly complex scoreboarding to hide the details of the pipelines from the instruction set model, onc
Mersenne Digest V1 #816
Mersenne Digest Tuesday, February 13 2001 Volume 01 : Number 816 -- Date: Sun, 11 Feb 2001 15:02:30 -0600 From: "Richard B. Woods" [EMAIL PROTECTED] Subject: Mersenne: FFT sizes in benchmark table headings, please? FFT sizes corresponding to exponent ranges seem not to be listed in the benchmark tables at http://www.mersenne.org/bench.htm and http://www.mersenne.org/overclk.htm. They _are_ listed in the rightmost column of the Search Status table at http://www.mersenne.org/status.htm. Could someone add FFT sizes to the benchmark table headings, please? _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 11 Feb 2001 16:30:59 EST From: [EMAIL PROTECTED] Subject: Mersenne: Re: P4 Optimization George Woltman wrote: George is working on it, but is a long way from completion. Progress is slow, primarily due to my own laziness. My estimate for a 512K FFT is 0.4 seconds on a 1.4GHz P4. You can compare that to other machines at http://www.mersenne.org/bench.htm. Jeff Woods wrote: Can we assume you meant 0.04? According to that site, A P-III 1.0 Ghz is already clipping such a number at 0.145, and a P4 is already listed there doing such in the current version at 0.126 See, there's afactor of 10 speedup already! :) Regarding the time estimate of 0.04 seconds per iteration at 512K FFT length, under optimal load conditions I've gotten around 0.12 sec/iter at this length with Mlucas running on a 500MHz Alpha 21264 with 4MB L2 cache. This is for compiled high-level source code, so scaling the closck speed up to 1.4GHz, subtracting a few tens of % for the smaller caches the L4 will come with initially, and adding them back for the boost hand-tuned assembly (at least in George's able hands) tends to yield, 0.04 seconds sounds about right for what is achievable. Still, even knowing that the current prototype code is likely quite far from optimal for the P4, a factor of ~3 speedup (0.126 -- 0.04 seconds) will be quite a challenge to realize. One of the drawbacks of doing it by hand in assembler...too bad high-quality HLL compilers (i.e. ones capable of giving 80-90% of the performance of laboriously coded and hand-tuned ASM, for complex, data-nonlocal algorithms requiring lots of data prefetch) appear to be nigh-impossible to write for CISCs like the x86 family. I don't want to start a RISC-versus-CISC flame war here, but the fact is, no high-level FFT-based large-integer-multiply code has gotten within a factor of 2 of the performance of Prime95 on the Pentium. - -Ernst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 11 Feb 2001 22:29:05 +0100 From: Henk Stokhorst [EMAIL PROTECTED] Subject: Mersenne: 39.000.000 range L.S., If anyone is working within the range 39.000.000 - 40.000.000, please contact me to avoid double work, I plan to delve for factors over there. YotN, Henk Stokhorst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 11 Feb 2001 18:12:12 -0500 From: Nathan Russell [EMAIL PROTECTED] Subject: Mersenne: P4 speed and implications thereof Let's assume that the P4 is, as George estimates, capable of doing the 512K FFT at 0.04 iterations per second. In this case, with some back-of-the-envelope calculations, I estimate that a thousand P4s (which might well be on PrimeNet in a year, or a little more - the P4 is approaching the status the Tbird was at a year ago, when I bought my current P3-600) could have done the entire 512K runlength in roughly 138 days, or under 5 months, even without the rest of the machines now contributing. Additionally, the P4 is only going to get faster in the next year or two. This frankly makes me wonder how much longer there will be a place in GIMPS for slower machines. I'm not saying that's a bad thing - after all, 486s and original pentiums were the workforce when GIMPS began, and I wouldn't feel comfortable with the amount of opportunity for error involved in using one for GIMPS now. Any comments from the list? Nathan _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 11 Feb 2001 18:48:21 -0500 From: Jud McCranie [EMAIL PROTECTED] Subject: Re: Mersenne
Mersenne Digest V1 #815
Mersenne Digest Sunday, February 11 2001 Volume 01 : Number 815 -- Date: Thu, 08 Feb 2001 19:35:26 -0800 From: "Terry S. Arnold" [EMAIL PROTECTED] Subject: Mersenne: P 4 Optimiztion I have heard rumblings that George has put together a version of the LL test optimized for the P 4. Does anyone know what the performance is like compared to a P 3? Terry Terry S. Arnold 2975 B Street San Diego, CA 92102 USA [EMAIL PROTECTED] (619) 235-8181 (voice) (619) 235-0016 (fax) _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 08 Feb 2001 23:09:51 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Re: Mersenne: P 4 Optimiztion Hi Terry, At 07:35 PM 2/8/2001 -0800, Terry S. Arnold wrote: I have heard rumblings that George has put together a version of the LL test optimized for the P4. Does anyone know what the performance is like compared to a P3? George is working on it, but is a long way from completion. Progress is slow, primarily due to my own laziness. My estimate for a 512K FFT is 0.4 seconds on a 1.4GHz P4. You can compare that to other machines at http://www.mersenne.org/bench.htm. As an aside, I've started putting together a document on what I'm learning about the P4 at http://www.mersenne.org/p4notes.doc I'll try to be more diligent... Happy hunting, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 08 Feb 2001 23:52:22 -0500 From: Jud McCranie [EMAIL PROTECTED] Subject: Re: Mersenne: P 4 Optimiztion At 07:35 PM 2/8/2001 -0800, Terry S. Arnold wrote: I have heard rumblings that George has put together a version of the LL test optimized for the P 4. Does anyone know what the performance is like compared to a P 3? The P4 doesn't do very well on the version that isn't optimized for the P4: http://www.mersenne.org/bench.htm +---+ | Jud McCranie | | | | Think recursively( Think recursively( Think recursively)) | +---+ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 08 Feb 2001 23:55:34 -0500 From: Jud McCranie [EMAIL PROTECTED] Subject: Re: Mersenne: P 4 Optimiztion At 11:09 PM 2/8/2001 -0500, George Woltman wrote: George is working on it, but is a long way from completion. Progress is slow, primarily due to my own laziness. My estimate for a 512K FFT is 0.4 seconds on a 1.4GHz P4. It probably isn't that important right now because few people have a P4. +---+ | Jud McCranie | | | | Think recursively( Think recursively( Think recursively)) | +---+ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 09 Feb 2001 12:07:48 -0500 From: Jeff Woods [EMAIL PROTECTED] Subject: Re: Mersenne: P 4 Optimiztion At 11:09 PM 2/8/01 -0500, you wrote: George is working on it, but is a long way from completion. Progress is slow, primarily due to my own laziness. My estimate for a 512K FFT is 0.4 seconds on a 1.4GHz P4. You can compare that to other machines at http://www.mersenne.org/bench.htm. Can we assume you meant 0.04? According to that site, A P-III 1.0 Ghz is already clipping such a number at 0.145, and a P4 is already listed there doing such in the current version at 0.126 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 09 Feb 2001 14:36:27 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Re: Mersenne: P 4 Optimiztion Hi, At 12:07 PM 2/9/2001 -0500, Jeff Woods wrote: My estimate for a 512K FFT is 0.4 seconds on a 1.4GHz P4. You can compare that to other machines at http://www.mersenne.org/bench.htm. Can we assume you meant 0.04? I wanted to make a safe
Mersenne Digest V1 #814
Mersenne Digest Thursday, February 8 2001 Volume 01 : Number 814 -- Date: Tue, 6 Feb 2001 15:15:29 -0600 From: "Levi Broderick" [EMAIL PROTECTED] Subject: Re: Mersenne: [screen saver] There's a rather good freeware screen saver written by Gianpaolo Bottin called GPhotoShow. It's just a slide show with transitions and provides a *lot* of free CPU time in between the pictures -- I run it along with Prime95 on this computer (450 pII) and there is no noticeable slowdown in either program on any priority setting. This could suffice unless a person wanted a GIMPS display integrated into the screen saver, though I'm not sure at all what there would be to display. Just throwing this out to the list. :) ~ Levi http://www.bottin.com/gpshow.htm - - Original Message - From: "Steve" [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, February 05, 2001 10:38 PM Subject: Re: Mersenne: Re: idea for a new prime95 version Excellent idea, Russ. I was discussing with Like Welsh the problem of people attached to their killer screensavers, and as he pointed out: "But maybe they'd watch pic of their kids/dog/vacation instead? The *particular* screensaver I was thinking of was the Photo Slide Show variety. Slap an image on the screen, wait 15 seconds, fade out, display another. Lots of free CPU time between pics." Certainly it won't work for everybody, but I'm sure there would be a lot of takers. Now, anybody know how to write such a thing? Could be released with the prime95/NT software or as a seperate item to be downloaded from the same site. Steve Harris _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 06 Feb 2001 21:44:31 + From: Gareth Randall [EMAIL PROTECTED] Subject: Re: Mersenne: [screen saver] Dear All, Let's face it, why should people who are primarily interested in mathematical computation divert their time to writing rather unimpressive screen savers? There are already plenty of programmers out there who can do that job better! So... Simply have an online list of "recommended" / "approved" / "suitable" screensavers. No-one has to write anything new. We just test those which already exist, and analyse what resource demands they make in terms of CPU usage, RAM access, process image size etc. Such a list can then allow contributors to select their preferred screensaver, and avoids introducing extra development complications. Yours, === Gareth Randall === _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 06 Feb 2001 18:30:01 -0500 From: Marc Getty [EMAIL PROTECTED] Subject: Mersenne: GIMPS SETI@Home Popularity Date: Sat, 03 Feb 2001 20:05:45 -0500 From: "Joshua Zelinsky" [EMAIL PROTECTED] Subject: Mersenne: Misc Stuff. A few minor comments. *snip* 5. One reason SETI is more popular is that they seem to have good media relations. Even if we could get a small mention of GIMPS in some non-math publication, the effect could be enormous. The Science Section of the NYT would be really amazing. Any thoughts? Long ago I got some local media coverage: http://getty.net/gimps/polec/ but I did not see any enormous GIMPS participation leaps locally I would have to agree that SETI is definitely more popular because it is "sexy". - -Marc Marc Getty [EMAIL PROTECTED] http://www.temple.edu/dentistry/di/ Department of Dental Informatics, Temple University School of Dentistry Phone: 215-707-8192Fax: 215-707-2208 New Dental School Room 311 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 6 Feb 2001 17:40:54 -0600 From: "Steve" [EMAIL PROTECTED] Subject: Re: Mersenne: [screen saver] Levi, does that GPhotoShow allow someone to use their own pictures? That's exactly what I was talking about. If so please let me know where I can get it. Some of you seem to misunderstand what I am getting at. I'm sure most serious contributors don't want a screensaver (I detest them), but in a situation where a friend or co-worker lets you install Prime95 on their PC but just HAS to have one (especially a really slow one), I would like to give them an option which: #1 - is Prime95 friendly and #2 - is easy to convince them to use. The "personal photo slide show" fits both of those criteria wonder
Mersenne Digest V1 #813
Mersenne Digest Tuesday, February 6 2001 Volume 01 : Number 813 -- Date: Sat, 3 Feb 2001 23:16:56 -0800 From: "Stephan T. Lavavej" [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #812 What about some of the new gaming platforms. I think some have computing capabilities equivalent to P133s and they have modem hookups. However, I'm not sure how feasible/worthwhile it would be to write progamrs to do this. Better yet, the Xbox. It will actually have a PIII-733 inside it, AND a hard drive, and a built-in broadband connection. All that would be required is the ability to run arbitrary code from the hard drive, and poof, you have something like a million potential boxes on which to run Prime95. Stephan T. Lavavej http://quote.cjb.net _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 4 Feb 2001 01:50:18 -0600 From: "Steve" [EMAIL PROTECTED] Subject: Re: Mersenne: idea for a new prime95 version "Alexander Kruppa" wrote: The screen-saver idea is important for another reason. I asked several coworkers and secretaries to let Prime95 (NTprime, actually) run on their PCs and they agreed, but they were less than happy when I asked them to change the pretty 3-d screen savers for something that lets NTprime have more cpu power. With the selection Microsoft offers right now, that means "Blank Screen" or "Marquee" - neither is extremely exciting to watch. Before long, most of them went back to the old screen savers and NTprime slowed down to a halt. "...slowed down to a halt" is no exaggeration. I've seen screensavers slow it down to more than 7 seconds per iteration at 800+ MHz. I have it running on some PCs where the user has the screensaver set to start after 5 minutes then sets the power management so the monitor turns off after 10 or 15 minutes... and what really bothers me is that the screensaver continues to run even with the monitor off. (Is there some way to prevent that which I don't know about?) One idiot even had her settings such that the screensaver didn't start until _after_ the monitor went off. There are so many screensavers available now that one can be found to match any personality, and I have found it impossible to get people to let go of one they really like. So I don't believe Brian's idea will do very much good; but then every little bit helps. Steve Harris [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 04 Feb 2001 00:16:03 -0800 From: Luke Welsh [EMAIL PROTECTED] Subject: Re: Mersenne: idea for a new prime95 version At 01:50 AM 2/4/01 -0600, Steve wrote: There are so many screensavers available now that one can be found to match any personality, Why not identify a couple of existing screensavers that could be "compatible" with Prime95 and then approach the author(s). ask them to make a verion that includes George's stuff? - --Luke _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 4 Feb 2001 14:36:05 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: idea for a new prime95 version, QA, primenet etc On 3 Feb 2001, at 17:03, Jeff Woods wrote: With increasing exponent size (and therefore run time), I'd like to see PrimeNet evolve to track intermediate residues also to be able to coordinate parallel LL testing double-checking, so that runs which are going wrong can be stopped for investigation without having to be run through to the end. I think this is an EXCELLENT idea, but remember that the "s" values (i.e. the intermediate residue/modulus) for such numbers is quite simply enormous. One couldn't (and shouldn't) check the entire intermediate value, but merely the last "x" bits, where "x" is enough to be reasonably certain that a match isn't random chance -- say, the final 1024 bits. 64 bits is enough to be pretty confident! We need a recovery procedure anyway, to cope with any systematic bugs which may exist. PrimeNet would thus also have to carefully assign the exponents to similar machines with similar runtimes and performance, as it would do little good to assign the primary test to an Athlon-800 and the "real-time" double-check to a much slower machine, as the Athlon would quickly outpace t
Mersenne Digest V1 #812
Mersenne Digest Saturday, February 3 2001 Volume 01 : Number 812 -- Date: Fri, 02 Feb 2001 15:24:43 +0100 From: mohk [EMAIL PROTECTED] Subject: Mersenne: idea for a new prime95 version hi there, the first idea is more an ideological one. the name is obsolet. :) i vote for winprime or prim4win. the next idea is to give the prime crunchers the choice of doin' what they want to do. for myself, i like to do double test. i could clean up the double tests to prove M(6972593) very fast (even faster than a some old pentiums). i have an tbird 800, and so i will get LLOne tests always. i could set another lame proc in the settings, but it isnt really the same. i'd be pleased to see in the next version a dialog where i can choose the test i wanna do. regards, mohk _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 2 Feb 2001 18:03:02 +0100 From: Lars Lindley [EMAIL PROTECTED] Subject: Re: Mersenne: idea for a new prime95 version Hi there mohk. I've soon been with the project for 2.5 years and there has always been a choice to set if you want primenet to choose a job for you or if you want to do LL, doublechecking or factoring. v19? added the option of 10 million digit LL:s too. You can find the settings under Primenet in the dropdown-menus. Win32Prime would be the correct name to use there since the name reflects what platform it runs on. Regards /Lars (It seems we need a new prime or nice milestone now. The list is virtually dead :( ) the first idea is more an ideological one. the name is obsolet. :) i vote for winprime or prim4win. the next idea is to give the prime crunchers the choice of doin' what they want to do. for myself, i like to do double test. i could clean up the double tests to prove M(6972593) very fast (even faster than a some old pentiums). i have an tbird 800, and so i will get LLOne tests always. i could set another lame proc in the settings, but it isnt really the same. i'd be pleased to see in the next version a dialog where i can choose the test i wanna do. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 03 Feb 2001 07:18:45 +0100 From: mohk [EMAIL PROTECTED] Subject: Re: Mersenne: idea for a new prime95 version Hi, again :) At 06:03 PM 02.02.01, you wrote: Hi there mohk. I've soon been with the project for 2.5 years and there has always been a choice to set if you want primenet to choose a job for you or if you want to do LL, doublechecking or factoring. v19? added the option of 10 million digit LL:s too. You can find the settings under Primenet in the dropdown-menus. Thanks, I found them, now. Win32Prime would be the correct name to use there since the name reflects what platform it runs on. Regards /Lars (It seems we need a new prime or nice milestone now. The list is virtually dead :( ) I thought a voting creates a new discussion, about increcements, odds etc. C'mon ppl, wake up and give a comment about improving the prime95 proggi. Mohk _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 3 Feb 2001 09:23:13 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: idea for a new prime95 version On 3 Feb 2001, at 7:18, mohk wrote: Win32Prime would be the correct name to use there since the name reflects what platform it runs on. I guess Prime95 comes from the "good old days" when Win95 was new and unqualified program names were expected to be 16-bit Win 3.x applications. BTW there still is a Win 3.x version of this program - I wonder if anyone's still using it??? But my vote's _against_ changing the name just for the sake of tracking fashion. What the program does is far more important than its name. We also have to bear in mind that some of the more obvious names have been picked up by other programs. (It seems we need a new prime or nice milestone now. The list is virtually dead :( ) OK, go find us one ;-) I thought a voting creates a new discussion, about increcements, odds etc. C'mon ppl, wake up and give a comment about improving the prime95 proggi. We need to remember what the function of the program is. It's designed to run unobtrusively in the background, and to have a low administrative overhead (be easy to set up, and easy to maintain). From this point of view, the existing program does an excellent jo
Mersenne Digest V1 #811
Mersenne Digest Saturday, January 27 2001 Volume 01 : Number 811 -- Date: Mon, 22 Jan 2001 14:53:44 -0500 (EST) From: Chip Lynch [EMAIL PROTECTED] Subject: Re: Mersenne: GIMPS slowdown due to California power problems? Well, I know it cost me a solid couple of days processing time for GIMPS. My apartment was apparently blacked out briefly while I was at work, and I've been turning my computers off in the evening to conserve, when normally they'd be on. The blackouts themselves have been brief, but they have happened. I'm in San Francisco, although most of the reports I've heard have been from just outside the bay area. - ---Chip On Mon, 22 Jan 2001 [EMAIL PROTECTED] wrote: I live in Southern California, and no blackouts have come out, yet. Everyone's been reporting that the main problem is in Northern California, San Francisco especially. San Diego Area has a good amount of power plants. Still, the people in California should, for the sake of fellow Californians, turn off their computers at 6pm, and turn them on at night shortly after the main usage time is over, 10pm. That is peak usage time, and we really don't want to use electricity at that time. That's also when rolling blackouts are issued. This summer, rolling blackouts could begin at the 6am - 8am period, a smaller spike that occurs. \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | | (202) 904-8570 (cell) | _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 23 Jan 2001 02:58:24 +0100 From: "Waclaw W. Psiurski" [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #808: Re: GIMPS in the News In Mersenne Digest Number 808 on Sunday, January 14 2001 Nathan Russell wrote on Mon, 08 Jan 2001 (...) While I think that's a tad too much criticism directed at a non-technical, local newspaper, and I know newspapers very rarely print any more than a retraction of 3 or 4 lines in an inside corner somewhere, I do have to dispute a few things said in that article: "Nor has anybody developed an easy way to tell whether a number is prime: Youve got to try dividing it by every possible factor, which is a time-consuming pain in the patoot." I think it's marginally possible to prove M127 in that fashion, but not M521 or any higher Mersenne. (...) The thesis in above quotation from a local newspaper is not quite true. A few monthes ago I found rather simple method (algorithm) for checking if any natural is prime or not and it is not under necessity of "to try dividing by every possible factor". It does not need to know anything about any odd primes less then examined natural n (exactly less then sqrt(n)). And I proved correctness of this method. But it is time-consuming. M521 is not so big - it is "only" in 521-bits arithmetic in comparison to e.g. 8-megabits arithmetic. - -- regards, Waclaw W. Psiurski [EMAIL PROTECTED] [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 27 Jan 2001 14:17:44 + From: Steve [EMAIL PROTECTED] Subject: Mersenne: Results didn't go back to the server: Recently my system failed to return a result back to the server, on my account it shows as being overdue, but I have this message in my results.txt: M8200667 is not prime. There was an error writing to the spool file and then it said (in the log file) that it would try to reconnect in 60 minutes, so I stopped mprime and started it again hoping that it would send the results, but it just got more work to do (I have moved house and didn't have net access for 3 weeks so ran out of work). Any suggestions or help greatly received. - -- Cheers Steve email mailto:[EMAIL PROTECTED] %HAV-A-NICEDAY Error not enough coffee 0 pps. web http://www.zeropps.uklinux.net/ or http://start.at/zero-pps 2:11pm up 13 days, 36 min, 2 users, load average: 1.02, 1.01, 1.00 _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------ End of Mersenne Digest V1 #811 **
Mersenne Digest V1 #810
Mersenne DigestMonday, January 22 2001Volume 01 : Number 810 -- Date: Fri, 19 Jan 2001 22:11:21 + (GMT) From: Russel Brooks [EMAIL PROTECTED] Subject: Mersenne: GIMPS slowdown due to California power problems? I wonder if GIMPS throughput will be noticeably reduced due to California's power problems? Either by people shutting their pcs off or being knocked off when hit by a rolling blackout? Cheers... Russ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 19 Jan 2001 18:56:36 -0600 From: [EMAIL PROTECTED] Subject: Re: Mersenne: GIMPS slowdown due to California power problems? I would be more worried about the servers since they are in San Diego. Imagine the possible data corruption. I wonder if GIMPS throughput will be noticeably reduced due to California's power problems? Either by people shutting their pcs off or being knocked off when hit by a rolling blackout? Cheers... Russ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 20 Jan 2001 10:19:03 + From: Gareth Randall [EMAIL PROTECTED] Subject: Re: Mersenne: GIMPS slowdown due to California power problems? Hopefully those responsible can reassure us that the servers are indeed running on high capacity UPS backup! A further question is what precautions the intermediate ISPs take to provide backup power for their leased line connections. Major hosting ISPs typically have enormous power backup facilities for their main systems, with diesel generators that can last days, but do they protect the routers for smaller leased lines such as the one which connects the GIMPS server in San Diego? [EMAIL PROTECTED] wrote: I would be more worried about the servers since they are in San Diego. Imagine the possible data corruption. I wonder if GIMPS throughput will be noticeably reduced due to California's power problems? Either by people shutting their pcs off or being knocked off when hit by a rolling blackout? Yours, === Gareth Randall === _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 22 Jan 2001 14:04:04 EST From: [EMAIL PROTECTED] Subject: Re: Mersenne: GIMPS slowdown due to California power problems? - --part1_51.671c1a4.279dde24_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit I live in Southern California, and no blackouts have come out, yet. Everyone's been reporting that the main problem is in Northern California, San Francisco especially. San Diego Area has a good amount of power plants. Still, the people in California should, for the sake of fellow Californians, turn off their computers at 6pm, and turn them on at night shortly after the main usage time is over, 10pm. That is peak usage time, and we really don't want to use electricity at that time. That's also when rolling blackouts are issued. This summer, rolling blackouts could begin at the 6am - 8am period, a smaller spike that occurs. - --part1_51.671c1a4.279dde24_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit HTMLFONT FACE=arial,helveticaFONT COLOR="#008080" SIZE=3 FAMILY="SCRIPT" FACE="Comic Sans MS" LANG="0"I live in Southern California, and no blackouts have come out, yet. BREveryone's been reporting that the main problem is in Northern California, BRSan Francisco especially. nbsp;San Diego Area has a good amount of power plants. nbsp; BRStill, the people in California should, for the sake of fellow Californians, BRturn off their computers at 6pm, and turn them on at night shortly after the BRmain usage time is over, 10pm. nbsp;That is peak usage time, and we really don't BRwant to use electricity at that time. nbsp;That's also when rolling blackouts are BRissued. nbsp;This summer, rolling blackouts could begin at the 6am - 8am period, BRa smaller spike that occurs./FONT/HTML - --part1_51.671c1a4.279dde24_boundary-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasa
Mersenne Digest V1 #809
Mersenne Digest Wednesday, January 17 2001 Volume 01 : Number 809 -- Date: Mon, 15 Jan 2001 11:06:08 -0600 From: "Griffith, Shaun" [EMAIL PROTECTED] Subject: Mersenne: List Archive? Are the list archives still kept somewhere? If not, does it make sense to move the list to a space that does? Recently the primenumbers list moved to egroups, for example. I don't know if that will satisfy our needs, or if there are other options. However, I haven't been able to search the archives in the usual places for posts more recently than February '98 (http://www2.netdoor.com/~acurry/mersenne/) or August '98 (http://www.scruz.net/~luke/archives/digest/). The New Zealand mirror page has been moved or removed. My personal archives go back to about January '98, though I haven't checked through them for completeness. It would be a shame if recent postings such as Peter-Lawrence Montgomery's excellent discourse on carry propagation remained lost to newcomers (and old hats who have purged their mail). I was just hoping to start a discussion on the state of the list archive. - -Shaun _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 15 Jan 2001 18:10:24 -0600 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: List Archive? "Griffith, Shaun" wrote: Are the list archives still kept somewhere? There is now an automatic archive on the web at http://www.egroups.com/group/mprime This is hosted by the commercial egroups mailing list service. Regards, Nathan Russell _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 15 Jan 2001 22:23:42 -0600 (CST) From: Conrad Curry [EMAIL PROTECTED] Subject: Re: Mersenne: List Archive? On Mon, 15 Jan 2001, Griffith, Shaun wrote: Are the list archives still kept somewhere? There are at least two and maybe more. Go to http://www2.netdoor.com/~acurry/mersenne/ and follow the links "To read more recent messages..." _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 16 Jan 2001 21:28:42 +1300 From: "Halliday, Ian" [EMAIL PROTECTED] Subject: Re: Mersenne: List Archive? "Griffith, Shaun" wrote: The New Zealand mirror page has been moved or removed. I maintained the New Zealand pages up to the beginning on 1998. Any links to them should have been removed by now. Regards, Ian - -- Ian W Halliday, BA Hons, MIMIS, AAIBF Snr, ATMB, CL +64 25 245 6089 http://baptism.co.nz Excel in all we do _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 17 Jan 2001 21:09:06 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: OT: Catalan's Conjecture Rhett tried sending this to the list, but I don't think it went through. From: Rhett Creighton [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Catalan's Conjecture Has anyone seen this? http://www.sciencenews.org/20001223/mathtrek.asp Catalan's Conjecture is now almost computationally reachable. I'm interested in starting a new distributive processing project to solve it, except that I estimate it will take around 300,000 pentium years. Though with seti power, that isn't too bad, or if we can think of a faster way to find double wiefrich primes. Hi ho! Rhett _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #809 **
Mersenne Digest V1 #807
Mersenne DigestSunday, January 7 2001Volume 01 : Number 807
--
Date: Wed, 03 Jan 2001 18:37:30 -0500
From: vincent mooney [EMAIL PROTECTED]
Subject: Re: Mersenne: Microsoft patents zeroes and ones
It's an old joke. That's why it is in The Onion.
At 05:58 PM 1/3/01 EST, Ernst wrote:
Check out
http://www.theonion.com/onion3311/microsoftpatents.html
At $0.10 per binary digit, the royalty fee GIMPS would
owe Microsoft for the last Mersenne prime is nearly
$70. Should we divide this equally amongst GIMPS
participants, or bill people proportionally to their
CPU-year contributions? I hope the fellow whose run
actually discovered the prime hasn't spent all his
EFF prize money yet...
On the plus side, such royalty fees are legitimately tax
deductible as business expenses. As usual, we can count
on Bill Gates to look out for the little guy. Thanks,
Bill!
-Ernst
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
--
Date: Fri, 5 Jan 2001 09:11:07 +0100 (MET)
From: [EMAIL PROTECTED]
Subject: Re: Mersenne: Understanding the Propagate Carry Step in the LL Test
Fix a length n. If (a0, a1, ..., a_(n-1)) and
(b0, b1, ..., b_(n-1)) are sequences of length n
(in some ring or field), then their circular convolution
is (c0, c1, ..., c_(n-1)) where
c_i = sum_{i == j + k mod n} a_j * b_k
For example, when n = 5, the circular convolution of
(a0, a1, a2, a3, a4) and (b0, b1, b2, b3, b4) is
(c0, c1, c2, c3, c4) where
c0 = a0*b0 + a1*b4 + a2*b3 + a3*b2 + a4*b1
c1 = a0*b1 + a1*b0 + a2*b4 + a3*b3 + a4*b2
c2 = a0*b2 + a1*b1 + a2*b0 + a3*b4 + a4*b3
c3 = a0*b3 + a1*b2 + a2*b1 + a3*b0 + a4*b4
c4 = a0*b4 + a1*b3 + a2*b2 + a3*b1 + a4*b0
The circular convolution is useful for polynomial
multiplication. Here, if
A(X) = a0 + a1*X + a2*X^2 + a3*X^3 + a4*X^4
B(X) = b0 + b1*X + b2*X^2 + b3*X^3 + b4*X^4
C(X) = c0 + c1*X + c2*X^2 + c3*X^3 + c4*X^4
then
A(X)*B(X) = C(X) + (X^5 - 1)(a1*b4 + a2*b3 + a3*b2 + a4*b1)
+ (X^6 - X)(a2*b4 + a3*b3 + a4*b2)
+ (X^7 - X^2)(a3*b4 + a4*b3)
+ (X^8 - X^3)(a4*b4)
== C(X) (mod X^5 - 1)
In general C(X) == A(X)*B(X) mod (X^n - 1).
By choosing n deg(A) + deg(B) (i.e., padding the input
polynomials with leading zero coefficients)
one can get their product exactly.
At first glance the computation of the ci's seems
to require n^2 multiplications and n(n-1) additions.
Techniques which I won't describe reduce this cost to O(n*log n) for large n.
If all ai and bi are integers, then so are the ci.
An upper on the ci is easily derived from upper bounds
on the ai and bi. Convolution algorithms which use
floating point (i.e., approximate) arithmetic
can estimate the largest potential error in the ci.
If this potential error is under 0.5, then one can
round the approximate ci to the nearest integers,
ensured one will get the correct results.
- - Large integer multiplication
When p is prime, the Lucas-Lehmer test for Mp = 2^p - 1
needs many squarings modulo Mp. How do we use the
circular convolution to assist us?
The task is to multiply two integers a, b in [0, Mp)
(or the closed interval [0, Mp] if we allow two
representations for 0 mod Mp), getting another such result.
We know the binary representations of a and b.
The textbook strategy first computes the double-length product a*b.
later reducing this modulo Mp. Choose a radix R (a power of 2)
and a length n such that R^n Mp. Write the inputs in radix R:
a = a0 + a1*R + ... + a_(n-1)*R^(n-1)
b = b0 + b1*R + ... + b_(n-1)*R^(n-1)
where all ai and bi are in [0, R-1).
[Or use signed digits in [-R/2, R/2].
Set ai = 0 and bi = 0 for n = i 2n.
Use a length-(2n) convolution to multiply the
corresponding polynomials A(X) and B(X) modulo X^(2n) - 1.
This will give the exact polynomial product since
deg(A) + deg(B) = (n-1) + (n-1) 2n.
The coefficients of this product are in [0, n*(R-1)^2] --
the convolution algorithm must produce accurate outputs
up to about n*R^2.
Let the output coefficients be
(c0, c1, ..., c_(2n-2), c_(2n-1)) where c_(2n-1) = 0.
To get the integer product c = a*b we set X = R
in the polynomial identity C(X) = A(X)*B(X).
Alas, the digits of C can exceed R-1.
We circumvent this by adding an appropriate multiple
of X-R to C(X). The loop resembles
carry := 0
for j from 0 to 2n-2 do
sum := carry + c_j
Mersenne Digest V1 #806
Mersenne Digest Wednesday, January 3 2001 Volume 01 : Number 806 -- Date: Sun, 31 Dec 2000 18:18:37 -0600 From: Nathan Russell [EMAIL PROTECTED] Subject: Mersenne: Shutdown script for mprime Hi, I was wondering if anyone knows of a script to shut down mprime and make sure the save files are finished saving before SIGKILL is sent in the shutdown process. In terms of starting it up, I now have a line in my inittab file to start it whenever the system enters runlevel 5, and run it with runtime options to use the Prime95 directory of the Windows drive as its working directory. It is set up to run setuid a user, and I've checked and it is indeed running as that user. Thanks! Nathan _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 31 Dec 2000 18:20:42 -0500 From: [EMAIL PROTECTED] Subject: Mersenne: Automatic reply I have moved. My new address is: [EMAIL PROTECTED] Please use this address in the future. Thanks _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 1 Jan 2001 00:46:48 +0100 (MET) From: [EMAIL PROTECTED] Subject: Re: Mersenne: 2000 - first calender year without a Mersenne Nathan Russell observes: Well, unless there is an announcement within the next few hours, 2000 will be the first calender year in the history of GIMPS without a Mersenne prime. Is the number of searchers, and the power of their hardware, increasing enough to keep up with the increased runtimes and (slightly) decreased chance of a given exponent being prime? Or can we expect only one prime every several years, as was the case before the start of the GIMPS effort? The chance that a given Mp is prime is O(1/log(Mp)) = O(1/p). The LL test for Mp needs O(p) iterations. The time per iteration (using an FFT) is about O(p*log(p)). So the estimated time per LL test is O(p^2 * log(p)) whereas the chance of success on one LL test is O(1/p). We need a few adjustments to the formula since (for example) the time to trial divide by primes N is approximately O(log(p) /p) for fixed N. [We test O(N/p) divisors below N, with a cost of O(log(p)) per divisor.] This trial division time decreases with p, whereas LL time increases, which affects our strategy. Nonetheless, to test all O(2^b / b) primes with b bits, we estimate O(2^b / b) * O(2^(2b) * b) = O(8^b) operations with O(1) expected successes. Doing all 24-bit p's takes about eight times as long as doing all 23-bit p's. Even with more contributors and faster hardware, we soon get diminishing returns. Peter Montgomery _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 31 Dec 2000 23:10:35 -0500 From: "Frank_A_L_I_N_Y" [EMAIL PROTECTED] Subject: Re: Mersenne: 2000 - first calender year without a Mersenne - - Original Message - From: "Frank_A_L_I_N_Y" [EMAIL PROTECTED] To: "Nathan Russell" [EMAIL PROTECTED] Sent: Sunday, December 31, 2000 7:53 PM Subject: Re: Mersenne: 2000 - first calender year without a Mersenne Even with hardware twice as fast, any current two year exponent would still take a year at that time. I don't think the rate of double the speed every two years can hold out for ever. Even if the next hardware can get through these exponents faster, the longer exponents would come down the pipe sooner, requiring the next hardware jump that much sooner. Regards Frank - Original Message - From: "Nathan Russell" [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Sunday, December 31, 2000 7:01 PM Subject: Mersenne: 2000 - first calender year without a Mersenne Well, unless there is an announcement within the next few hours, 2000 will be the first calender year in the history of GIMPS without a Mersenne prime. Is the number of searchers, and the power of their hardware, increasing enough to keep up with the increased runtimes and (slightly) decreased chance of a given exponent being prime? Or can we expect only one prime every several years, as was the case before the start of the GIMPS effort? This might be a good discussion, since the list is fairly quiet now. Nathan _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -
Mersenne Digest V1 #805
Mersenne Digest Sunday, December 31 2000 Volume 01 : Number 805 -- Date: Fri, 29 Dec 2000 15:48:21 -0500 From: [EMAIL PROTECTED] Subject: Mersenne: Automatic reply I have moved. My new address is: [EMAIL PROTECTED] Please use this address in the future. Thanks _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 31 Dec 2000 18:01:32 -0600 From: Nathan Russell [EMAIL PROTECTED] Subject: Mersenne: 2000 - first calender year without a Mersenne Well, unless there is an announcement within the next few hours, 2000 will be the first calender year in the history of GIMPS without a Mersenne prime. Is the number of searchers, and the power of their hardware, increasing enough to keep up with the increased runtimes and (slightly) decreased chance of a given exponent being prime? Or can we expect only one prime every several years, as was the case before the start of the GIMPS effort? This might be a good discussion, since the list is fairly quiet now. Nathan _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #805 **
Mersenne Digest V1 #804
Mersenne Digest Friday, December 29 2000 Volume 01 : Number 804 -- Date: Fri, 22 Dec 2000 17:07:12 -0500 From: [EMAIL PROTECTED] Subject: Mersenne: Automatic reply I have moved. My new address is: [EMAIL PROTECTED] Please use this address in the future. Thanks _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 22 Dec 2000 18:10:41 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: Re: PrimeNet DB Sychro Complete Happy Holidays to all, At 01:54 PM 12/22/2000 -0800, Scott Kurowski wrote: Some of you may have noticed your Cleared Exponents lists are shorter following Wednesday's PrimeNet resync with George's database. Thanks for hanging in there for 10 months instead of the usual 3 between updates. Due to a quirk in the way we synchronize databases, some LL test results remain in the cleared exponents list. Exponents below 8,000,000 that still need to be double-checked are affected by this odd behavior. Good luck to all in 2001, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 23 Dec 2000 10:31:56 + From: Gareth Randall [EMAIL PROTECTED] Subject: Mersenne: Overclocking - bad for project? There are occasional announcements about overclocking various processors, and I know that some Mersenne contributors describe their clock speed as xxx@yyy where yyyxxx obviously. However, surely this project is one where overclockers do more harm than good? When you're running your favourite game, it doesn't matter if a couple of incorrect calculations creep in, but the Mersenne project involves very long calculations with basically a boolean answer at the end. One wrong result during this time could ruin the answer. Now I know that the algorithms include a lot of error catching, but once the processor is run to the point of instability there could easily be errors in the error protection. (I'll try a probability analysis later... Basically we need the probability of one error occurring within a certain number of instructions of a previous error.) My opinion is that it's better to have fewer correct results than to have the central database poisoned by loads of "don't think it's prime, but the user was overclocking" results, which of course cannot be distinguished from perfect answers. I'd trade two unreliable answers for one honest result. (What ends up happening is even worse. Mismatching checksums mean that the tests must be repeated until a consensus is reached.) A high score table is brilliant, and excites all contributors, but unfortunately a few seem more interested in climbing the table than in what the project is about. If people want to run overclocked, they should work on a project which isn't so sensitive to noise, such as SETI (okay, hardly an original suggestion here). SETI takes a noisy input to begin with, and introducing the odd bit of noise won't harm the results that much. People whose machines show any sign of instability at all should really stick to factoring, although these are just the sort of people who'll be issued with primality tests because of the apparently high performance. I'm tempted to say: go and find another high score table to climb. So after all that, here's a suggestion: How about an error counting system in mprime/prime95? (Okay there might already be one but I haven't seen it mentioned anywhere.) Every time an error is detected, a counter is incremented, and the final result sent back to the server. An answer coming back with 200 errors might be considered less reliable than one with no errors at all. Yours, === Gareth Randall === _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 23 Dec 2000 11:08:47 -0500 From: Jud McCranie [EMAIL PROTECTED] Subject: Re: Mersenne: Overclocking - bad for project? At 10:31 AM 12/23/2000 +, Gareth Randall wrote: However, surely this project is one where overclockers do more harm than good? When you're running your favourite game, it doesn't matter if a couple of incorrect calculations creep in, but the Mersenne project involves very long calculations with basically a boolean answer at the end. ... I agree. I've never overclocked my computers because I think it is more important to be confident in the results. +-+ | Ju
Mersenne Digest V1 #803
Mersenne Digest Friday, December 22 2000 Volume 01 : Number 803 -- Date: Wed, 20 Dec 2000 06:36:53 -0500 From: [EMAIL PROTECTED] Subject: Mersenne: Automatic reply I have moved. My new address is: [EMAIL PROTECTED] Please use this address in the future. Thanks _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 20 Dec 2000 15:06:14 -0800 From: xqrpa [EMAIL PROTECTED] Subject: Mersenne: The P4: An Overclocking Guide This is a multi-part message in MIME format. - --=_NextPart_000_0006_01C06A96.6570BDE0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable And to think 200 MHz used to seem fast... See the following link for rich rewards: http://www.gamepc.com/reviews/hardware_review.asp?review=3Dp4ocpage=3D1= mscssid=3Dtp=3D Best Wishes, Stefanovic - --=_NextPart_000_0006_01C06A96.6570BDE0 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC -//W3C//DTD HTML 4.0 Transitional//EN HTMLHEAD META content=3Dtext/html; charset=3Diso-8859-1 = http-equiv=3DContent-Type META content=3DMSHTML 5.00.2614.3500 name=3DGENERATOR STYLE/STYLE /HEAD BODY bgColor=3D#ff DIVAnd to think 200 MHz used to seem fast.../DIV DIVnbsp;/DIV DIVSee the following link for rich rewards:/DIV DIVnbsp;/DIV DIVA=20 href=3Dhttp://www.gamepc.com/reviews/hardware_review.asp?review=3Dp4oca= mp;page=3D1amp;mscssid=3Damp;tp=3Dhttp://www.gamepc.com/reviews/hardw= are_review.asp?review=3Dp4ocamp;page=3D1amp;mscssid=3Damp;tp=3D/A/D= IV DIVnbsp;/DIV DIVBest Wishes,/DIV DIVStefanovic/DIV/BODY/HTML - --=_NextPart_000_0006_01C06A96.6570BDE0-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 22 Dec 2000 13:54:58 -0800 From: Scott Kurowski [EMAIL PROTECTED] Subject: Mersenne: PrimeNet DB Sychro Complete Hi all, Some of you may have noticed your Cleared Exponents lists are shorter following Wednesday's PrimeNet resync with George's database. Thanks for hanging in there for 10 months instead of the usual 3 between updates. We have had a few things on our plate here. In case you have not been following Entropia's amazing progress this year as a commercial distributed computing services company, please visit our web site and check out the Press section. We expect 2001 to be an even bigger year. If you are near San Diego, please feel free to drop in for a visit. We love meeting people from the Mersenne list! (Right Luke?) (Please note that Entropia 2000, our general-purpose distributed computing software, is not yet compatible with Prime95 or NTPrime... which take CPU time from Entropia 2000, so try not to run them concurrently! :-) Just as we have since late 1997, we look forward to our continued role supporting GIMPS into the future. On behalf of the entire Entropia team, we'd like to wish everyone a great holiday season. Best wishes happy hunting, Scott Kurowski Brad Bernard Entropia, Inc. [EMAIL PROTECTED] (scott) [EMAIL PROTECTED] (brad) _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #803 **
Mersenne Digest V1 #802
Mersenne Digest Wednesday, December 20 2000 Volume 01 : Number 802 -- Date: Mon, 18 Dec 2000 00:52:35 -0800 From: "John R Pierce" [EMAIL PROTECTED] Subject: Mersenne: primenet synchronization Is it just me, or have we not had a database sync for a long time between George and primenet? my personal results file on primenet is showing values going back to March... Also, just noted this one... 11765981 73 F 9413069237925298809767 13-Dec-00 15:58 p3-500 its been so long, does that mean I found a factor of a rather large candidate? cool, haven't had one of those in AGES (over a year anyways). _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 18 Dec 2000 01:02:50 -0800 From: Paul Leyland [EMAIL PROTECTED] Subject: RE: Mersenne: primenet synchronization Is it just me, or have we not had a database sync for a long time between George and primenet? my personal results file on primenet is showing values going back to March... Nope, it's everyone. Mine go back to 6827629 63 0x7B026BBFAEE5C7__01-Feb-00 16:00 ROUGE How about it George? An update in time for the millenium? Also, just noted this one... 11765981 73 F 9413069237925298809767 13-Dec-00 15:58 p3-500 10441463 76 F96784719665374106986817 01-Dec-00 16:46 RED its been so long, does that mean I found a factor of a rather large candidate? cool, haven't had one of those in AGES (over a year anyways). Yup. The one above is my first this year. It trumps yours ;-) Paul _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Wed, 20 Dec 2000 12:18:03 +0100 From: michel claes [EMAIL PROTECTED] Subject: Mersenne: How to start NTPrime on logout ? Dear all, My network administrator agees that I run NTPrime at the office when nobody is logged on the machines (NT4). Did anyone in this list have already done this ? If yes, how ? Here are my solutions. 1) the more efficient. - - Start NTPrime when the machine boot (±easy). - - Start NTPrime when the user logs out. I don't know how to do that. Can you help me ? - - Stop NTPrime when the user logs on. Send stop message to NTPrime or use KILL.EXE from the NT resource kit. 2) Easy to implement - - Shedule NTPrime to run every M,T,W,Th,F at 7:00 PM. - - Shedule a kill NTPrime every M,T,W,Th,F at 7:00 AM. I have installed solution 2 with success on a test machine. But NTPrime is not running during hollidays (public + presonnal) 40 days / year = 480 ours of computiong losts. Thanks in advance for your comments. Michel. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #802 **
Mersenne Digest V1 #801
Mersenne Digest Sunday, December 17 2000 Volume 01 : Number 801 -- Date: Fri, 15 Dec 2000 09:00:33 -0800 From: "Richard J. Otter" [EMAIL PROTECTED] Subject: Mersenne: RE: Mersenne Digest V1 #800 I haven't seen any news posted on the mersenne.org home page lately. I'm wondering about the status of the project. Are we running out of steam? I I alone in feeling a bit discouraged about finding another mersenne prime soon? Richard Otter _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 16 Dec 2000 07:49:51 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: RE: Mersenne Digest V1 #800 On 15 Dec 00, at 9:00, Richard J. Otter wrote: I haven't seen any news posted on the mersenne.org home page lately. Presumably because nothing especially significant has happened? I'm wondering about the status of the project. Are we running out of steam? No, judging by the rate at which completed tests are being submitted to PrimeNet :) I I alone in feeling a bit discouraged about finding another mersenne prime soon? Finding another prime is probably just about due on a statistical basis ... but we might or might not be lucky, it could possibly be several years before another is found. The one thing that is certain is that, if effort is withdrawn, finding that next prime will be delayed! Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 16 Dec 2000 07:49:52 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: factoring the higher exponents On 15 Dec 00, at 10:39, Henk Stokhorst wrote: I spend the past months factoring the range 16.000.000 up to 17.000.000 form 2^52 up to 2^58. I reported the results once a week, which are included in the database. This week someone else started to work on this as well although up to 2^56. This work is therefor done twice. What is being done and can be done to avoid this? Well, if people would stick to PrimeNet assignments, this sort of thing wouldn't happen... At least the other "culprit" is bothering to report the results, and the duplicated effort isn't too much - only about one quarter of your investment. BTW would anyone who has run P-1 on exponents in the range 10 to 125000 (prime, with no known factors) without reporting the limits used please report them to me. I'm working through them with B1=1E6, B2=25E6 but seem not to be finding any factors - possibly someone has done them before? Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 16 Dec 2000 19:15:06 -0500 (EST) From: Jason Stratos Papadopoulos [EMAIL PROTECTED] Subject: Mersenne: n_th roots of 2 in a finite field? Hello. I'm putting the finishing touches on a large-integer convolution library that's optimized for the Alpha ev6, and I want to build support for Mersenne-mod convolution right into the library. However, the library is integer-only and works with integers modulo a 62-bit prime (eventually several 62-bit primes, once I code up Chinese remainder convolution). This means that in order to perform DWT arithmetic I have to find n_th roots of 2 in a finite field modulo a given prime, where n is a large power of two. I have no clue how to do this. Nick Craig-Wood's page gives some hints for the special case of 2^64-2^32+1, but not enough for me to apply the theory to other primes. It looks like you need to find primes p so that (p-1)/(order of 2 mod p) has a large power of 2 as a factor. 62-bit primes where this is the case seem quite rare; I've found only 14 primes of this size that allow a Mersenne DWT of size 2^22 or more (out of a billion candidates). But now I need some way to figure out the actual root of two. Can anybody point me in the right direction? jasonp PS: This code promises to be the fastest integer-only LL test available. It's already producing runtimes in the ballpark of floating point code, and will improve more when I add CRT code and optimize more heavily. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 17 Dec 2000 22:03:24 +0100 (MET) From: [EMAIL PROTECTED]
Mersenne Digest V1 #800
Mersenne Digest Friday, December 15 2000 Volume 01 : Number 800 -- Date: Sun, 10 Dec 2000 01:32:27 -0600 From: "Richard B. Woods" [EMAIL PROTECTED] Subject: Mersenne: Caution about P4 future I urge those of you contemplating a Pentium 4 purchase to read a cautionary note about its future written by Thomas Pabst, author of "Tom's Hardware Guide" at http://www.sysdoc.pair.com Basically, Pabst has written that if you buy a Pentium 4 before next summer, you may not be able to upgrade the processor alone to a faster P4 later on. According to him, Intel plans to change both the P4 chipset and socket in mid-2001; Intel will still produce P4s after mid-2001, but those won't be motherboard-compatible with the current version of P4. Now, if you know you won't ever want to upgrade only your P4 processor without also upgrading the motherboard, or you don't mind having to buy a new motherboard in order to use a faster P4, then this is not relevant. Otherwise, have a look at the part of Pabst's Intel roadmap article at http://www.sysdoc.pair.com/cpu/00q4/001013/roadmap-02.html subtitled "Pentium 4 'Willamette' Is Just A Short-Term Filler". Richard Woods _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 10 Dec 2000 11:32:50 -0500 (EST) From: [EMAIL PROTECTED] Subject: Re: Mersenne: Caution about P4 future I urge those of you contemplating a Pentium 4 purchase to read a cautionary note about its future written by Thomas Pabst, author of "Tom's Hardware Guide" at http://www.sysdoc.pair.com Basically, Pabst has written that if you buy a Pentium 4 before next summer, you may not be able to upgrade the processor alone to a faster P4 later on. According to him, Intel plans to change both the P4 chipset and socket in mid-2001; Intel will still produce P4s after mid-2001, but those won't be motherboard-compatible with the current version of P4. Now, if you know you won't ever want to upgrade only your P4 processor without also upgrading the motherboard, or you don't mind having to buy a new motherboard in order to use a faster P4, then this is not relevant. Otherwise, have a look at the part of Pabst's Intel roadmap article at http://www.sysdoc.pair.com/cpu/00q4/001013/roadmap-02.html subtitled "Pentium 4 'Willamette' Is Just A Short-Term Filler". Richard Woods _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sun, 10 Dec 2000 13:07:27 -0500 (EST) From: Jason Stratos Papadopoulos [EMAIL PROTECTED] Subject: Re: Mersenne: Caution about P4 future On Sun, 10 Dec 2000, Richard B. Woods wrote: I urge those of you contemplating a Pentium 4 purchase to read a cautionary note about its future written by Thomas Pabst, author of "Tom's Hardware Guide" at http://www.sysdoc.pair.com Anyone contemplating a P4 purchase and in need of second, third and fourth opinions should use DejaNews to track down all the discussions in comp.sys.ibm.pc.hardware.chips on whether the P4 is a good thing or not at this time. In particular you'll find out that Tom's opinion has flip-flopped about three times on the P4. jasonp _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 11 Dec 2000 09:51:49 -0600 From: "Richard B. Woods" [EMAIL PROTECTED] Subject: Re: Mersenne: Caution about P4 future Jason Stratos Papadopoulos has alerted me to my not having sufficiently delimited the scope of my previous P4 future cautionary note in its topic paragraph rather than its final paragraph. That, alas, was a particular example of a persistent weakness in my communication skills. I apologize for it. If I were to recompose my previous message, its topic paragraph would be more like: For those of you contemplating a Pentium 4 purchase -- If you won't ever want to upgrade your P4 processor without also upgrading the motherboard, or if you won't mind having to buy a new motherboard in order to upgrade to a faster P4, then this message is not relevant for you. OTOH, if you want to be able to upgrade your P4 processor without having to buy a new motherboard, I urge you to read a caut
Mersenne Digest V1 #799
Mersenne Digest Saturday, December 9 2000 Volume 01 : Number 799 -- Date: Thu, 7 Dec 2000 14:30:16 -0800 From: "xqrpa" [EMAIL PROTECTED] Subject: Mersenne: P4 Overclocking Benchmarks And Much Else This is a multi-part message in MIME format. - --=_NextPart_000_002E_01C0605A.37C8BF00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To All: An in-depth look at the P4 using ASUS P4T mobo, with overclocking to 1.7xy GHz, can be found at: http://www.gamepc.com/reviews/hardware_review.asp?review=3Dasusp4tpage=3D= 1mscssid=3Dtp=3D Best Wishes, Stefanovic - --=_NextPart_000_002E_01C0605A.37C8BF00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" HTMLHEAD META content=3D"text/html; charset=3Diso-8859-1" = http-equiv=3DContent-Type META content=3D"MSHTML 5.00.2614.3500" name=3DGENERATOR STYLE/STYLE /HEAD BODY bgColor=3D#ff DIV DIVTo All:/DIV DIVnbsp;/DIV DIVAn in-depth look at the P4 using ASUS P4T mobo, with/DIV DIVoverclocking to 1.7xy GHz, can be found at:/DIV DIVnbsp;/DIV DIVA=20 href=3D"http://www.gamepc.com/reviews/hardware_review.asp?review=3Dasusp4= tamp;page=3D1amp;mscssid=3Damp;tp=3D"http://www.gamepc.com/reviews/ha= rdware_review.asp?review=3Dasusp4tamp;page=3D1amp;mscssid=3Damp;tp=3D= /A/DIV DIVnbsp;/DIV DIVBest Wishes,/DIV DIVStefanovic/DIV DIVnbsp;/DIV DIVnbsp;/DIV/DIV/BODY/HTML - --=_NextPart_000_002E_01C0605A.37C8BF00-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Mon, 4 Dec 2000 20:52:51 +0100 From: "Dawor" [EMAIL PROTECTED] Subject: Mersenne: per interation time values 1. Sorry for my english 2. Prime95 is working on my 2 computers. On one of them (P120MHz 40MB) values "per interation time" are always different (0.753, 0.710, 0.734 ...) and on the other (K6II 350 64) that values are always the same (0.530, 0.530 ). It's so when I'm not working on the maschine so I don't think that it's infuence of another program. What is the cause of that??? thx 4 help Davv0r Buy a Pentium IV Processor so you can reboot faster! _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Sat, 9 Dec 2000 14:49:15 -0800 From: "xqrpa" [EMAIL PROTECTED] Subject: Mersenne: Prime Real Estate: The AMD "Mustang" Core Will Do Even More This is a multi-part message in MIME format. - --=_NextPart_000_000A_01C061EF.33BBD640 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Bon Weekend To All! With the American election yo-yo still in full career, and Prime95 optimizations for the P4 well in the works, a look at what AMD has in store for us may be of interest: See http://www.aceshardware.com/Spades/list_news.php?category=3DAMD for some light weekend reading... Best Wishes, Stefanovic - --=_NextPart_000_000A_01C061EF.33BBD640 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" HTMLHEAD META content=3D"text/html; charset=3Diso-8859-1" = http-equiv=3DContent-Type META content=3D"MSHTML 5.00.2614.3500" name=3DGENERATOR STYLE/STYLE /HEAD BODY bgColor=3D#ff DIVBon Weekend To All!/DIV DIVnbsp;/DIV DIVWith the American election yo-yo still in full career,/DIV DIVand Prime95 optimizations for the P4 well in the works,/DIV DIVa look at what AMD has in store for us may be of interest:/DIV DIVnbsp;/DIV DIVSee/DIV DIVnbsp;/DIV DIVA=20 href=3D"http://www.aceshardware.com/Spades/list_news.php?category=3DAMD"= http://www.aceshardware.com/Spades/list_news.php?category=3DAMD/ABR/= DIV DIVfor some light weekend reading.../DIV DIVnbsp;/DIV DIVBest Wishes,/DIV DIVStefanovicBR/DIV/BODY/HTML - --=_NextPart_000_000A_01C061EF.33BBD640-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #799 **
Mersenne Digest V1 #798
Mersenne Digest Thursday, December 7 2000 Volume 01 : Number 798 -- Date: Tue, 5 Dec 2000 12:44:04 -0600 From: "Griffith, Shaun" [EMAIL PROTECTED] Subject: Mersenne: System Recovery Mess I have recently been upgraded at work to a P3/733 (wow!). However, I have discovered that I have a mess in my Prime95 directory. I would like some help clearing it up, but I don't want to waste any work in progress. The worktodo.ini file reads thusly: Test=11604521,64,1 and Prime95 is diligently plowing ahead on this. However, I have the following files in the directory that might not have finished because of the system rebuild did not reinstate the entire directory intact: mB601731 mB604521 p5196601 q5196601 qB604521 The results.txt file indicates that M5196601 is not prime, so I am pretty sure I can get rid of that (but I'm saving it for now). My old machine does not have any outstanding exponents checked out (according to my account page). My new machine only has one exponent checked out, the one it is working on: 11604521. Thanks, Shaun _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 7 Dec 2000 13:47:20 -0800 From: "xqrpa" [EMAIL PROTECTED] Subject: Mersenne: P4 Overclocking Benchmarks And Much Else This is a multi-part message in MIME format. - --=_NextPart_000_0007_01C06054.3865F820 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To All: An in-depth look at the P4 using ASUS P4T mobo, with overclocking to 1.7xy GHz, can be found at: http://www.gamepc.com/reviews/hardware_review.asp?review=3Dasusp4tpage=3D= 1mscssid=3Dtp=3D Best Wishes, Stefanovic - --=_NextPart_000_0007_01C06054.3865F820 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" HTMLHEAD META content=3D"text/html; charset=3Diso-8859-1" = http-equiv=3DContent-Type META content=3D"MSHTML 5.00.2614.3500" name=3DGENERATOR STYLE/STYLE /HEAD BODY bgColor=3D#ff DIVTo All:/DIV DIVnbsp;/DIV DIVAn in-depth look at the P4 using ASUS P4T mobo, with/DIV DIVoverclocking to 1.7xy GHz, can be found at:/DIV DIVnbsp;/DIV DIVA=20 href=3D"http://www.gamepc.com/reviews/hardware_review.asp?review=3Dasusp4= tamp;page=3D1amp;mscssid=3Damp;tp=3D"http://www.gamepc.com/reviews/ha= rdware_review.asp?review=3Dasusp4tamp;page=3D1amp;mscssid=3Damp;tp=3D= /A/DIV DIVnbsp;/DIV DIVBest Wishes,/DIV DIVStefanovic/DIV/BODY/HTML - --=_NextPart_000_0007_01C06054.3865F820-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- End of Mersenne Digest V1 #798 **
Mersenne Digest V1 #797
Mersenne DigestSunday, December 3 2000Volume 01 : Number 797 -- Date: Fri, 01 Dec 2000 00:13:25 EST From: [EMAIL PROTECTED] Subject: Re: Mersenne: P4 Jason Papadopoulos wrote: The alpha was already at least 5x faster than a PIII for multiprecision arithmetic at the same clock speed; with the P4 it will only get worse. Brian Beesley replied: Are you sure about this? I think, with Alpha, you have to execute the instruction twice to get a double-precision multiplication - you can store either the low half or the high half of a product in one instruction, but not both. True, you need two instructions to get both halves of a 64x64 == 128-bit product on the Alpha. It always seemed wasteful to me to have an instruction (e.g. Alpha umulh) to get the upper half a product, which simply discards the lower half - by way of contrast, MIPS dmult calculates the full 128-bit product in one shot, returning the result in *two* 64-bit integer registers - but apparently the Alpha designers wanted all instructions to be in 2-input, one-output-register format, no exceptions. You might say they felt it would be less than RISCy to do otherwise. Now, on the Alpha 21064, integer muls are unpipelined and slow, so getting a 128-bit product takes around 30 cycles. On the 21164 imuls are partially pipelined - one can start at most every 8 cycles - so a double-width product needs around 16 cycles, very close to what the MIPS needs using its unpipelined dmultu instruction. Now on the Alpha 21264, imuls still have fairly long latency (I believe around 6-8 cycles) but are *fully* pipelined, so even with the need to use 2 instructions to do it, one can effectively get a 128-bit product every 2 cycles, which really screams. The IA-64 will (from what I've read) actually be very much like the 21264 in this respect: 2 instructions for the separate halves of a double-wide integer product (the IA-64 analog of Alpha umulh is called xma.hu), but here the muls will use the x86-style floating multiplier, whose 64-bit mantissa is of convenient length for 64-bit integer multiply. Thus, imuls will benefit from the fact that the fmul unit is already designed to have fairly low latency and, more importantly, is highly pipelined. How is any of this relevant to Mersenne testing? Well, fast 64-bit integer ops should make a well-designed all-integer convolution algorithm competitive with a floating-point-FFT-based one. However, neither of these two is truly satisfying since each basically uses just half the functionality (integer or floating-point) of the processor. We really need an algorithm that does floating and integer convolutions in parallel and uses some method (e.g. Chinese remainder theorem or some other form of error correction) to recorrelate the two result vectors at the end of each convolution step. Such methods are feasible, but highly nontrivial to implement, and even more challenging to implement efficiently. Stay tuned... - -ernst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 01 Dec 2000 01:08:46 EST From: "Chris Nash" [EMAIL PROTECTED] Subject: Re: Mersenne: Factoring Hi folks, Off-topic I know, but... We could let prime95 decide the next election grin. Give everybody a different prime number. Multiply the primes for candidate A together, likewise for B. And like in this election, unless we can completely factor the results, we wouldn't know who won, either. :) _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 1 Dec 2000 07:22:24 +0100 (MET) From: [EMAIL PROTECTED] Subject: Re: Mersenne: Factoring Chris Nash proposed: We could let prime95 decide the next election grin. Give everybody a different prime number. Multiply the primes for candidate A together, likewise for B. And like in this election, unless we can completely factor the results, we wouldn't know who won, either. No need to factor during primery elections. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Fri, 1 Dec 2000 02:54:35 -0800 From: Paul Leyland [EMAIL PROTECTED] Subject: RE: Mersenne: Factoring We could let prime95 decide the next election grin. Give everybody a different prime number. Multiply the primes for candidate A together, likewise for B. And like in this election, unless we can completely factor the results, w
Mersenne Digest V1 #796
Mersenne Digest Thursday, November 30 2000 Volume 01 : Number 796 -- Date: Tue, 28 Nov 2000 15:48:11 -0500 From: "Willmore, David (VS Central)" [EMAIL PROTECTED] Subject: RE: Mersenne: P4 - a correction George wrote: One correction to my previous post. I said that the latency to access the L1 data cache was 2 clocks. This is correct for integer instructions only. For floating point and SSE2 instructions the latency is 6 clocks! Interestingly, the L2 cache latency is 7 clocks for both integer and floating point instructions. Look at the coupling that the FPU has to the cache for one reason. I would expect that the FPU(s) have more ports on the L1 than that integer units do. Also, if you look at the sensitivity of different types of code to load latency, integer code, by far, is more sensitive than floating point. Think about the length of the floating point pipeline, it's pretty long to start with, so you're gonig to *have* to unroll your code to take advantage of the pipeline, so you might as well cover the additional load to use latency the same way. With enough rename registers, it's all good. :) Cheers, David _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 28 Nov 2000 16:48:13 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: Re: P4 - a correction Hi, At 07:45 AM 11/28/00 +, Brian J. Beesley wrote: Surely the latency is much less relevant than the throughput, provided that there are sufficient registers and pipeline entries. True. The manuals are unclear as to how many XMM registers are available. There are 8 user visible ones and an unknown number of internal ones that you use via the P4's register renaming feature. The idea is to keep the execution units busy ... I just finshed designing the new code for one of the easier problems - the rounding and carry propagation step after the inverse FFT. It looks like the P4 can do this in 6.5 clocks per double vs. about 19 clocks per double on the P3. This doesn't count any benefits from prefetching data. It also seems that the multiply units are idle enough in the new code so that I can continue to use the compact two-to-fractional-power arrays, rather than two full 5MB arrays. Thus, yesterday's question of 33MB max is probably 23MB max for a 640K FFT. That's good, because I'd feel guilty using up 33MB. Heck, I feel guilty using 23MB. I don't expect the above savings (3 times fewer clocks) to hold for the FFT code. The old FFT code was much better pipelined than the old carry propagation code. Bear in mind that there may be a severe penalty for switching between SSE2 and x86 FPU formats. There is no penalty on the P4. The XMM registers do not overlap the FPU registers in the same way that MMX registers do. Having fun, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Tue, 28 Nov 2000 14:06:41 -0800 From: "Stephan T. Lavavej" [EMAIL PROTECTED] Subject: Mersenne: More on Compression This 'Wonderful' compression technology maybe "Awesome"; however, MY main objection or perhaps philosophy towards all of this is that Prime95 is not a large piece of code. It takes a relatively small amount of time to download over a modem compared to other software items that we modem users may download in a weeks period. Maybe if Prime95 was ..say .. a 20MB download. Then perhaps shaking things up to save some download time would be a good idea, but as things stand now we are only talking about saving 20 or so seconds. Perhaps that is the reason people may find it 'objectionable'.. Maybe its just not worth the hassle at the moment for this particular application Actually, the download time wouldn't change all that much. (The package would go from 400K to 300K.) But the executable itself, once unzipped, would only be some 200K, as compared to over 1MB before. It's just more efficient. The question is, if compression involves a one-time, five-minute cost on the part of the developer and saves everyone a few seconds of download time and a few K of HD space, then why not? Why have bloated code? I sure like looking at 200K executables instead of megabyte and larger things. Makes me think of my old 486 where everything fit in 120MB. P.S. The website for the compression program never resolved for me; I'd like to take a look at it, if someone would send me the IP. http://upx.tsx.org is a redirection URL for http://wildsau.idv.uni-linz.ac.at/mfx/upx.html. The P4 at 1.5 GHz is ju
Mersenne Digest V1 #795
Mersenne Digest Tuesday, November 28 2000 Volume 01 : Number 795 -- Date: Sun, 26 Nov 2000 22:45:41 +0100 From: "Hoogendoorn, Sander" [EMAIL PROTECTED] Subject: Mersenne: OT: Home Primes A bit Off Topic, but i finaly had time to put some data i have of Home Primes (I.E. repeated factorizations of concatenated prime factors) online. In case you're interested http://www.geocities.com/home_primes _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 26 Nov 2000 15:06:40 -0800 From: "Stephan T. Lavavej" [EMAIL PROTECTED] Subject: Mersenne: Compressing Prime95 I discovered something interesting. The most recent Prime95 executable is very large, 1212928 bytes long. However, if I use UPX (Ultimate Packer for eXecutables, upx.tsx.org) with the --best option, I can compress Prime95 down to 238542 bytes! That's about 20% of its original size. The compression process, happily, is invisible to the end user, and incurs no time or memory cost; the compressed Prime95 behaves just as the original did. Saving space is always a good idea. This compression is actually better than ZIP compression, so when the distribution zipfile includes the smaller executable, it too becomes smaller: from 405953 bytes to 299756 bytes. This makes the download go quicker for everyone, which especially matters to modem users, but is nice even for people with fast connections. Awesome. Stephan T. Lavavej _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 26 Nov 2000 23:25:09 +0100 (MET) From: [EMAIL PROTECTED] Subject: Re: Mersenne: P4 Hi all, The mailing list has been quiet. I hope everyone enjoyed a happy Thanksgiving (or at least a good weekend for non-U.S. readers). The focus has been on double-checking, by a different mechanism than that which made the original count, alas in a non-Mersenne context. I've received 2 queries about the recently released Pentium 4 and prime95. I have no timings at this point, but I figured some folks would like to know how the architecture helps or hurts our cause. I've downloaded the manuals and have the following observations: (stuff deleted) 2) The P4 introduces SSE2 instructions. Intel hopes new programs stop using the old FPU instructions and start using these new instructions. The SSE2 instructions work on 2 floating point values at the same time! An ADD takes 4 clocks, but can only issue every other clock cycle. A MUL takes 6 clocks and also can be issued every other clock cycle. The theoretical maximum throughput for SSE2 is one ADD *AND* one MUL every clock cycle. The average latency is 2 for a ADD and 3 for a MUL. Summary: If a program can be effectively recoded to use SSE2, then it can have greater throughput than even the Athlon. Of course, months ago I had hoped that the P4 would be able to get a throughput of 2 ADDs and 2 MULs per clock cycle. Maybe in a few years, a future P4 or AMD chip will do this. I understand that the SSE2 instructions operate only on 64-bit (and 32-bit) floating point data, whereas the FPU registers support 80-bit intermediate results. How will the loss of precision affect the FFT length? Vector processors such as the Cray typically support both vector op vector - vector vector op scalar - vector opcodes, so one can (for example) form all b[i]^2 - 4.0*a[i]*c[i] when solving several quadratic equations. [We need two vector*vector multiplications, one vector*scalar multiplication, one vector-vector subtraction.] I find it strange that the MMX and XMM and SSE2 instruction sets lack vector*scalar operations and also lack a way to make multiple copies of the constant 4.0, other than to store multiple copies in memory. While data replication in memory (or adding a[i]*c[i] to itself twice) may be acceptable here, we don't want multiple copies of the table of roots of unity, for example. Peter Montgomery _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 27 Nov 2000 10:40:52 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: Compressing Prime95 On 26 Nov 00, at 15:06, Stephan T. Lavavej wrote: Saving space is always a good idea. This compression is actually better than ZIP compression, so when the
Mersenne Digest V1 #794
Mersenne Digest Sunday, November 26 2000 Volume 01 : Number 794 -- Date: Fri, 17 Nov 2000 14:21:23 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Re: Mersenne: Shortage on double-check exponents Hi all, 5 PM 11/17/00 +0100, Canart, Jean-Yves wrote: Since a few days, there are no more available exponents for double-checking. Sorry 'bout that. I've made 9600 new exponents available. Those doing first -time tests on exponents between 6,100,000 and 6,500,000 are *still* doing first time tests even though the primenet server will now report them as double-checking assignments. Regards, George _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Fri, 17 Nov 2000 16:34:16 -0500 From: Matt Gauthier [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #793 distributed.net is a simpel brute force, for the mathematics behind mersenne.o rg see: http://www.mersenne.org/math.htm ok,ok, there is no use for such primes, but mathematics is - like life itself - l'art pour l'art anyway. Apart from RC5, and the other inane crypto contests, distributed.net is also searching for the optimal 24 and 25 mark Golomb rulers. So, there is a purely mathematical project there too. - -- Matt Gauthier [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 26 Nov 2000 16:32:45 -0500 From: George Woltman [EMAIL PROTECTED] Subject: Mersenne: P4 Hi all, The mailing list has been quiet. I hope everyone enjoyed a happy Thanksgiving (or at least a good weekend for non-U.S. readers). I've received 2 queries about the recently released Pentium 4 and prime95. I have no timings at this point, but I figured some folks would like to know how the architecture helps or hurts our cause. I've downloaded the manuals and have the following observations: 1) The FPU is slower than the P-III. An FADD is 5 clocks (vs. 3 on P-III and 4 on Athlon). An FMUL is 7 clocks (vs. 5 on P-III and 4 on Athlon). An FADD can be issued every clock cycle. An FMUL can be issued every other clock cycle (same as P-III, Athlon can issue every clock cycle). An FADD and FMUL cannot be started on the same clock cycle (same as the P-III, no such restriction on Athlon). Summary: On paper, Athlon still has the best FPU, P-III next, P4 last (but remember the P4 has the faster clock). 2) The P4 introduces SSE2 instructions. Intel hopes new programs stop using the old FPU instructions and start using these new instructions. The SSE2 instructions work on 2 floating point values at the same time! An ADD takes 4 clocks, but can only issue every other clock cycle. A MUL takes 6 clocks and also can be issued every other clock cycle. The theoretical maximum throughput for SSE2 is one ADD *AND* one MUL every clock cycle. The average latency is 2 for a ADD and 3 for a MUL. Summary: If a program can be effectively recoded to use SSE2, then it can have greater throughput than even the Athlon. Of course, months ago I had hoped that the P4 would be able to get a throughput of 2 ADDs and 2 MULs per clock cycle. Maybe in a few years, a future P4 or AMD chip will do this. 3) The memory layout in the P4 has changed greatly. This will require careful recoding in prime95. a) The L1 data cache has been reduced to 8K - the same size as the original Pentium. The L1 cache is faster than previous chips (2 clocks vs. 3 clocks). b) The L1 cache has 64 byte cache lines. This means fewer cache line loads from the L2 cache. c) The L2 cache is very fast: 7 clcoks. I don't know the number for previous chips, but I'm sure it was higher. d) The L2 cache has 128-byte cache-lines, meaning few cache line loads from main memory. e) There are instructions to prefetch cache lines from main memory into the L2 cache. The P-III had a similar instructions but Prime95 never used them. f) Initial P4 machines will use RDRAM. Without getting into the Rambus holy war, P4 machines will generally have higher memory bandwidth but access time to the first byte of a memory request is slower. Summary: With proper recoding, prime95 may make significant gains. Proper use of the prefetch instructions can hide most of the waiting on main memory that you see with the current version. Furthermore, there are several places in prime95 where I chose to tradeoff extra floating point operations in order to reduce memory accesses. Using more memory on the P4 (and fewer floating point operations) will probably make more sense. Finally, I've ordered a P4 which
Mersenne Digest V1 #793
Mersenne Digest Friday, November 17 2000 Volume 01 : Number 793
--
Date: Wed, 15 Nov 2000 07:58:56 -0800
From: Paul Leyland [EMAIL PROTECTED]
Subject: Mersenne: The factorization of P773, or 2^773+1
Several members of the GIMPS team responded to my request earlier this year
to attempt ECM factoring of the number P773. Several thousand curves with
B1=11M and B1=44M failed to find a factor. The reason for this failure can
be seen in the announcement below; the earlier work gave a 50% chance of
finding a 48-digit factor (had there been one) and only a very tiny chance
of finding the 55-digit factor actually present. Nonetheless, the work was
valuable and convinced the The Cabal that P773 was a worthy target for a
record-breaking SNFS factorization.
The Cabal's announcement of their success follows.
Paul
-
233-digit SNFS factorization
-
``The Cabal'' announces the completion, on November 14, 2000,
of the factorization with the Special Number Field Sieve (SNFS)
of the 233-digit Cunningham number 2,773+ = 2^773 + 1 into the product
of 3, 533371 and three primes of 55, 71, and 102 digits, respectively.
This establishes a new record for the Special Number Field Sieve SNFS.
The previous SNFS record was the 211-digit repunit number
10,211- = (10^211 - 1)/9, factored on April 8, 1999, also by the Cabal.
Details are available from:
ftp://ftp.cwi.nl/pub/herman/SNFSrecords/SNFS-233.
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt
--
Date: Fri, 17 Nov 2000 12:25:19 +0100
From: "Bjoern Hoffmann" [EMAIL PROTECTED]
Subject: Mersenne: RE: [2600-AU] distributed.net, Mersenne.org
dave wrote:
For those who don't know: like SETI@Home but you can use your
CPU's idle
time for different 'projects' and be able to win prizes and stuff.
much better and much more sophisticated: www.mersenne.org,
looking for great primes ...
I don't know if I can argue about it being better, but it's
definitely not more
sophisticated.
Come on :) everyone knows how to find primes -- and to get big
primes you'd use 2^n+1 trick
to find them quicker.
distributed.net is a simpel brute force, for the mathematics behind mersenne.org see:
http://www.mersenne.org/math.htm
ok,ok, there is no use for such primes, but mathematics is - like life itself - l'art
pour l'art anyway.
cu
Bjoern
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt
--
Date: Fri, 17 Nov 2000 12:25:14 +0100
From: "Bjoern Hoffmann" [EMAIL PROTECTED]
Subject: Mersenne: FW: [2600-AU] distributed.net, Mersenne.org
from 2600-Australia
cu
Bjoern
- -Original Message-
From: KevinL [mailto:[EMAIL PROTECTED]]
Sent: Thursday, November 16, 2000 12:34 PM
To: [EMAIL PROTECTED]
Subject: Re: [2600-AU] distributed.net, Mersenne.org
This makes me laugh - the'profile' of a program finding prime numbers would
presumably be similar to the 'profile' of a program cracking crypto. What are
they using your machine for again - and who's "they" exactly? ;)
('profile' in dits because I'm not quite sure how you'd profile a program of
that sort in any useful way - but the concept remains)
KL
(When does paranoia stop being healthy?)
"Bjoern Hoffmann" wrote
Sime wrote:
For those who don't know: like SETI@Home but you can use your CPU's idle
time for different 'projects' and be able to win prizes and stuff.
much better and much more sophisticated: www.mersenne.org, looking for great
primes ...
cu
Bjoern
-
The name of this list is: [EMAIL PROTECTED]
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
Note: Comments to this mailing list are owned by the poster
KevinL
- -
The name of this list is: [EMAIL PROTECTED]
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
Note: Comments to this mailing list are owned by the poster
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt
--
Date: Fri, 17 Nov 2000 17:35:46 +0100
From: "Canart, Jean-Yves" [EMAIL PROTECTED]
Subject: Mersenne: Shortage on double-check exponents
Hello all !
Since a few days, there a
Mersenne Digest V1 #792
Mersenne Digest Tuesday, November 14 2000 Volume 01 : Number 792 -- Date: Sun, 12 Nov 2000 13:57:05 -0800 From: Matthew Ashton [EMAIL PROTECTED] Subject: Re: Mersenne: Script to run mprime as a system daemon. On Sun, Nov 12, 2000 at 12:08:25PM +, Gareth Randall wrote: I have been running mprime on Linux for some time and have recently written a script to make it run as a daemon on startup. mprime automatically nice's itself, which is very neat and makes it ideal for running this way. On my Debian 2.2 system: snip Hi Gareth, I would just like to point out that mprime has been available as part of Debian based Linux distributions for quite a while. apt-get install prime-net Version 19.1 is in Debian 2.2 (potato) and version 20.6 is available for woody. It is probably worth mentioning that it is part of Debian on www.mersenne.org (as prime-net). The Debian woody package can be found here: http://ftp.debian.org/dists/woody/non-free/binary-i386/misc/prime-net_20.6.2-2.deb Thanks go to Francois Gouget [EMAIL PROTECTED] for putting this in Debian. Go Debian! :-) - --- Matthew Ashton [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 12 Nov 2000 17:18:10 -0800 From: "xqrpa" [EMAIL PROTECTED] Subject: Mersenne: Prime Time: L-L Test Doesn't Exist? This is a multi-part message in MIME format. - --=_NextPart_000_000B_01C04CCC.8839C2A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To All: In case you missed the article "Prime Time" in New Scientist, the URL = is: https://www.newscientist.com/features/features.jsp?id=3Dns226444 The author goes on to write: "Even so, it is mathematics that will gain the most. "Right now, when we = tackle problems without knowing the truth of the Riemann hypothesis, = it's as if we have a screwdriver," says Sarnak. "But when we have it, = it'll be more like a bulldozer." For example, it should lead to an = efficient way of deciding whether a given large number is prime. No = existing algorithms designed to do this are guaranteed to terminate in a = finite number of steps. " Well, the L-L Test seems to be just such an algorithm. Best Wishes, Stefanovic - --=_NextPart_000_000B_01C04CCC.8839C2A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" HTMLHEAD META content=3D"text/html; charset=3Diso-8859-1" = http-equiv=3DContent-Type META content=3D"MSHTML 5.00.2614.3500" name=3DGENERATOR STYLE/STYLE /HEAD BODY bgColor=3D#ff DIVTo All:/DIV DIVnbsp;/DIV DIVIn case you missed the article "Prime Time" in New Scientist, the = URL=20 is:/DIV DIVnbsp;/DIV DIVA=20 href=3D"https://www.newscientist.com/features/features.jsp?id=3Dns226444"= https://www.newscientist.com/features/features.jsp?id=3Dns226444/A/DI= V DIVnbsp;/DIV DIVThe author goes on to write:/DIV DIVnbsp;/DIV DIV P class=3Djustify"Even so, it is mathematics that will gain the most. = "Right=20 now, when we tackle problems without knowing the truth of the Riemann=20 hypothesis, it's as if we have a screwdriver," says Sarnak. "But when we = have=20 it, it'll be more like a bulldozer." For example, it should lead to an = efficient=20 way of deciding whether a given large number is prime. No existing = algorithms=20 designed to do this are guaranteed to terminate in a finite number of = steps.=20 "/P P class=3DjustifyWell, the L-L Test seems to be just such an = algorithm./P P class=3DjustifyBest Wishes,/P P class=3DjustifyStefanovic/P P class=3Djustifynbsp;/P P class=3Djustifynbsp;/P P class=3Djustifynbsp;/P/DIV/BODY/HTML - --=_NextPart_000_000B_01C04CCC.8839C2A0-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 12 Nov 2000 20:54:57 -0500 From: Nathan Russell [EMAIL PROTECTED] Subject: Re: Mersenne: Prime Time: L-L Test Doesn't Exist? To be fair, the quote says that it is difficult to determine the primarlity of 'a given large number'. Only an infentesimal fraction of arbitrary large numbers are Mersenne, or other special forms like 'Proth' primes. Nathan xqrpa wrote: To All: In case you missed the article "Prime Time" in New Scientist, the URL is: https://www.newscientist.com/features/features.jsp?id=ns226444 The author goes
Mersenne Digest V1 #791
Mersenne Digest Sunday, November 12 2000 Volume 01 : Number 791
--
Date: Thu, 09 Nov 2000 19:04:58 -0800
From: Eric Hahn [EMAIL PROTECTED]
Subject: Mersenne: Companies form Distributed Computing Alliance
Hewlett-Packard, Compaq Computer and SGI have joined with
distributed computing software seller Platform Computing and
a host of other companies to standardize the way computers are
harnessed into distributed computing collections
Full story at:
http://news.cnet.com/news/0-1003-200-3586486.html
Eric
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt
--
Date: Sun, 12 Nov 2000 12:08:25 +
From: Gareth Randall [EMAIL PROTECTED]
Subject: Mersenne: Script to run mprime as a system daemon.
I have been running mprime on Linux for some time and have recently written a script
to make it run as a daemon on startup. mprime automatically nice's itself, which is
very neat and makes it ideal for running this way.
On my Debian 2.2 system:
Copy the enclosed script to: /etc/init.d/mprime.sh
You need to then create symlinks in the following locations:
/etc/rc0.d/K01mprime
/etc/rc1.d/K01mprime
/etc/rc2.d/S99mprime
/etc/rc6.d/K01mprime
Don't forget rc6.d! I did at first and spent some time being very confused.
Points to bear in mind:
Running mprime in a separate user account may be a good idea. This is because:
1. It is protected from anything you may do in your own user space. You can't
accidently kill it or delete its files. In the script I am running it as myself,
although this is a whole lot better than root.
2. Depending on your file permissions, other user accounts would be protected in the
unlikely case of there being a destructive bug in mprime, or any sort of exploitation
from the remote server. (Okay, the latter is very unlikely, but I work in Internet
security so it's always on my mind!)
Where compute intensive tasks are running:
1. Although not explicitly tested I presume that both tasks would be penalised by the
scheduler down to the lowest priority, and hence each would get 50% of the remaining
CPU time. This would impact any performance intensive games, for instance, so running
mprime as a daemon may not be such a good idea if you need to be able to turn it on
and off regularly.
2. The performance penalty will be worse than this, because some cache thrashing would
occur as the scheduler switches between tasks.
I have also included my earlier prime.sh script which I wrote for manually controlling
the mprime program. This is what I used before deciding the daemonise it. I made some
improvements for the daemon which aren't in this script, but you can edit those in.
I've pasted the scripts inline as I'm not sure whether attachments are allowed.
Start of mprime.sh
#!/bin/sh
#
# mprime.sh Script to manage "mprime" prime factoring program.
#
# Version: 1.1 11-Nov-2000 Gareth Randall
#
PRIME_BIN_FILE=/home/gareth/mprime/mprime
PRIME_LOG_FILE=/home/gareth/mprime/log/mprime.log
DESC="prime factoring program"
NAME=mprime
if !(test -f $PRIME_BIN_FILE) ; then
echo "Couldn't find $NAME binary: $PRIME_BIN_FILE" 2
exit 1;
fi
case "$1" in
start)
if (pidof $PRIME_BIN_FILE /dev/null ) ; then
echo "ABORTING: Process with that binary already running!" 2
exit 1;
fi
echo -n "Starting $DESC: "
echo -n "START: " $PRIME_LOG_FILE
date $PRIME_LOG_FILE
su gareth -c "$PRIME_BIN_FILE -d $PRIME_LOG_FILE "
echo "$NAME."
;;
stop)
echo -n "Stopping $DESC: "
killall -2 $PRIME_BIN_FILE
echo -n "STOP : " $PRIME_LOG_FILE
date $PRIME_LOG_FILE
echo "$NAME."
;;
*)
echo "Usage: $0 {start|stop}" 2
exit 1
;;
esac
exit 0
End of mprime.sh
Start of prime.sh
#!/bin/sh
PRIME_BIN_FILE=/home/gareth/mprime/mprime
PRIME_LOG_FILE=/home/gareth/mprime/log/mprime.log
if (pidof $PRIME_BIN_FILE) ; then
echo "ABORTING: A process with that executable is already running!"
exit 1;
fi
if !(test -f $PRIME_BIN_FILE) ; then
echo "Couldn't find mprime binary: $PRIME_BIN_FILE"
exit 1;
fi
date $PRIME_LOG_FILE
$PRIME_BIN_FILE -d | tee -a $PRIME_LOG_FILE
End of prime.sh
Hope someone finds these useful!
Yours,
=== Gareth Randall ===
_
Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt
--
End of Mersenne Digest V1 #791
**
Mersenne Digest V1 #790
Mersenne Digest Tuesday, November 7 2000 Volume 01 : Number 790 -- Date: Thu, 2 Nov 2000 06:41:09 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: Mersenne: ECM update -- M727 finished up to 50 digits On 1 Nov 00, at 18:17, David A. Miller wrote: The last machine that I had working on M727 has finished its 1000 curves at B1=44M. This is enough to finish the recommended number of curves at that bound. Thus there are probably no factors below 10^50, and it won't be practical to find the factors with ECM. The question arises as to whether or not it is economical to continue beyond B1=4400, B2=429000. This may be a function of the native integer size - 64-bit systems shouldn't have any problems (given a suitable implementation) I guess the special number field people will take an interest as soon as they've cleared whatever they're working on at the moment. Have any other numbers received as much ECM effort as this? I'm betting that there aren't many. Possibly not - even if the curves for B1=4400 B2=429000 have been done, they've probably been done on a smaller exponent, therefore with less expenditure of time. Although the curves completed don't look as good, it is, however, possible that more CPU time has been expended trying to factor some of the Fermat numbers using ECM. There's still plenty of work for you to do! Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 2 Nov 2000 10:18:52 + From: Alexander Kruppa [EMAIL PROTECTED] Subject: Re: Mersenne: ECM update -- M727 finished up to 50 digits "Brian J. Beesley" wrote: The question arises as to whether or not it is economical to continue beyond B1=4400, B2=429000. This may be a function of the native integer size - 64-bit systems shouldn't have any problems (given a suitable implementation) I have a hacked version of mprime that uses another prime sieve (the primegen library), it will let you go all the way to B1=2^32, B2~=2^60. It seems to work alright but I havent given it too much testing yet - I've had little time recently. If there is any demand out there from truely desparate ECM factorers, I'll try to make a releasable version. Have any other numbers received as much ECM effort as this? I'm betting that there aren't many. [...] Although the curves completed don't look as good, it is, however, possible that more CPU time has been expended trying to factor some of the Fermat numbers using ECM. I think F14 beats even M727. I've done a lot of curves at B1=3M and B1=11M, if I recall correctly, one B1=11M took about 11 hours on a PII-400, so the 5200*3M + 1270*11M plus smaller curves should add up to something like 30.000 cpu hours, while M727 (1 hour per 44M curve) has around 25.000 hours accumulated. Ciao, Alex. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Tue, 07 Nov 2000 22:32:47 EST From: [EMAIL PROTECTED] Subject: Mersenne: New Mlucas binary for Sparc Thanks to Bill Rea, we now have a new, improved Mlucas 2.7a binary for Sparc Solaris (2.6 and above; I've also run it successfully under SunOS). On a 333 MHz Ultra II I have at work, my 2000-iteration timings for an exponent around 5.9M (320K FFT length) dropped from 9 to 7 minutes. Thanks, Bill! ftp://hogranch.com/pub/mayer/README.html Happy hunting, - -Ernst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt ------ End of Mersenne Digest V1 #790 **
Mersenne Digest V1 #789
Mersenne Digest Wednesday, November 1 2000 Volume 01 : Number 789 -- Date: Mon, 30 Oct 2000 12:36:12 + From: Gordon Spence [EMAIL PROTECTED] Subject: Mersenne: Re: Output from nofactor.cmp On Mon, 30 Oct 2000 Henk Stokhorst wrote Subject: Mersenne: bug in Wordpad? L.S., Whenever I have a large file (about 3.000 lines) with exponents to test (extracted from the nofactor.cmp file) and replace all the 'Test=' with 'Factor=' using wordpad (part of windows accesoires) one line gets to read 'Factorst='. When I extract items from this file using decomp.exe from George, then ALL of the lines already say Factor= How are you extracting them? regards G _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 30 Oct 2000 07:43:09 -0800 From: "John R Pierce" [EMAIL PROTECTED] Subject: Re: Mersenne: bug in Wordpad? It is not really the OS (although UNIX does have a lot of nice tools for this type of thing) it is wordpad that is not really the most capable text editor. If you are using Windows I would suggest you try TextPad which is available for 30 day evaluation from www.textpad.com. another very good ascii editor is 'Ultraedit32', also available for free evaluation. http://www.ultraedit.com - -jrp _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 30 Oct 2000 18:22:29 +0100 From: "Steinar H. Gunderson" [EMAIL PROTECTED] Subject: Mersenne: Re: bug in Wordpad? On Mon, Oct 30, 2000 at 07:43:09AM -0800, John R Pierce wrote: another very good ascii editor is 'Ultraedit32', also available for free evaluation. http://www.ultraedit.com While EditPad (http://www.editpad.com/, I think, not quite sure) is postcardware (ie. send a postcard to the author :-) ). Optionally, if you're into Unix and vi, vim (www.vim.org) is of course available in DOS and Windows versions :-) /* Steinar */ - -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 30 Oct 2000 19:18:24 +0100 From: Henk Stokhorst [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Output from nofactor.cmp Gordon Spence wrote: When I extract items from this file using decomp.exe from George, then ALL of the lines already say Factor= How are you extracting them? with the wrong parameter, -t instead of -w ;-) YotN, Henk Stokhorst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Tue, 31 Oct 2000 10:42:11 +0100 From: "Hoogendoorn, Sander" [EMAIL PROTECTED] Subject: RE: Mersenne: bug in Wordpad? Whenever I have a large file (about 3.000 lines) with exponents to test (extracted from the nofactor.cmp file) and replace all the 'Test=' with 'Factor=' using wordpad (part of windows accesoires) one line gets to read 'Factorst='. You can extract with the -w option to get Factor= infront of each line see the readme file _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Tue, 31 Oct 2000 11:16:00 + From: Alexander Kruppa [EMAIL PROTECTED] Subject: Mersenne: ECM better than O(sqrt(f)) ? I've read on the list some time ago that ECM takes, like Pollard-Rho or P-1, O(sqrt(f)) operations mod N to find a factor f. But looking at the factors found so far I find that hard to believe; according to that formula, finding a 50-digit factor should be 10^15 times harder than finding a 20-digit factor. Even if a 20-digit could be found in 1 sec. average, the 50-digit would take some 30 million years - I dont believe this much time has been spent on ECM worldwide already. Is ECM better than O(sqrt(f)) ? Are there any more accurate lower bounds, or even a \Theta(g(f)) ? Ciao, Alex. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Tue, 31 Oct 2000 03:51:53 -0800 From: Paul Leyland [EMAIL PROTECTED] Subject:
Mersenne Digest V1 #788
Mersenne DigestMonday, October 30 2000Volume 01 : Number 788 -- Date: Sat, 28 Oct 2000 09:45:20 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Re: RE: Mersenne: Volunteers wanted Hi guys, I now have complete results of this project. Altogether there were 17 segments of one million iterations each. All but one of these matched the original run. There was a mismatch between iterations 8.3 million and 8.4 million. Rerunning this segment on the original system resulted in an interim residual which matched the value reported by the user who ran this segment. Conclusions: (a) My system "glitched" once during the original run. Quite honestly this surprised me as the system is not significantly overclocked, is well cooled, is fitted with ECC memory and has no history of single- bit memory errors corrected by ECC. Nor has it ever crashed, hung up or spontaneously rebooted. Therefore I feel it's more than likely that the glitch was memory corruption caused by a software problem. This system is running Windows 2000 Professional ... (b) There is no evidence of any systematic difference between Athlon and Intel processor families which might affect the GIMPS/PrimeNet project. Thanks again to the participants! Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 29 Oct 2000 13:59:37 -0800 From: "Ethan Hansen" [EMAIL PROTECTED] Subject: RE: RE: Mersenne: Volunteers wanted A possible explanation is a soft error in one of the processors internal caches. These can be caused either by cosmic rays, or alpha decay within the lead solder bumps. As processors incorporate more internal cache, not only on die L1, but the 32 - 128K of other instruction caches, the possibility of these errors increases. A study using 2MB cache Xeon processors detected no errors at sea level equvalent cosmic ray flux, some problems at 1 mile altitude, and serious ( 1 fault per month) at 4 miles. Moral of the story: don't bring your laptop along while climbing Mt Everest. Regards, Ethan - -Original Message- [SNIP] Conclusions: (a) My system "glitched" once during the original run. Quite honestly this surprised me as the system is not significantly overclocked, is well cooled, is fitted with ECC memory and has no history of single- bit memory errors corrected by ECC. Nor has it ever crashed, hung up or spontaneously rebooted. Therefore I feel it's more than likely that the glitch was memory corruption caused by a software problem. This system is running Windows 2000 Professional ... (b) There is no evidence of any systematic difference between Athlon and Intel processor families which might affect the GIMPS/PrimeNet project. Thanks again to the participants! Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 30 Oct 2000 10:26:27 +0100 From: Henk Stokhorst [EMAIL PROTECTED] Subject: Mersenne: bug in Wordpad? L.S., Whenever I have a large file (about 3.000 lines) with exponents to test (extracted from the nofactor.cmp file) and replace all the 'Test=' with 'Factor=' using wordpad (part of windows accesoires) one line gets to read 'Factorst='. Can other people reproduce this result? What OS would you recommend for such operations ;-) YotN, Henk Stokhorst _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 30 Oct 2000 11:13:05 - From: "Andy Hedges" [EMAIL PROTECTED] Subject: FW: Mersenne: bug in Wordpad? Henk Stokhorst, It is not really the OS (although UNIX does have a lot of nice tools for this type of thing) it is wordpad that is not really the most capable text editor. If you are using Windows I would suggest you try TextPad which is available for 30 day evaluation from www.textpad.com. Hope this helps, Andy ~~ ~~ Andy Hedges Consultant Proteus the Internet Consultancy Tel: + 44 (0)207 689 Fax: + 44 (0)207 689 6667 Direct: + 44 (0)207 689 6669 Web: http://www.proteus.co.uk Email: [EMAIL PROTECTED] 26 Britton St, London EC1M 5UB A Division of Proteus Ventures Ltd Registered in England: 3169362 VAT: 675007732 ~~ ~~ - -Original Message
Mersenne Digest V1 #787
Mersenne Digest Thursday, October 26 2000 Volume 01 : Number 787 -- Date: Sat, 21 Oct 2000 19:49:59 +0200 (CEST) From: Henrik Olsen [EMAIL PROTECTED] Subject: Re: Mersenne: Exponent already completed? What probably happened is that the exponent was first assigned to another, whose machine didn't check in in 60 days, which meant the exponent got reassigned to you. The original machine then finished the check and send in the result. You don't need to do anything, once your machine finish it'll send in the result and you'll get credited with a doublecheck and the full CPU time. On Thu, 19 Oct 2000, Siegmar Szlavik wrote: Hi, same problem here... exponent 10590059. Working on it since 3 weeks or so. Is it safe to leave the machine untouched, ignore the error messages and let it finish the exponent or do I have to make some changes to the .ini files to be sure the server doesn't reject the exponent when the work is done? Siegmar One of my machines just dropped off my assigned machine list. Also that machine is saying "ERROR 11" Exponent already completed. How did this happen? This machine has been working on this exponent for two weeks. The exponent is 10544533. I checked the competed exponent list and the user "LAKE_COMMS" claims to have completed it on Oct 5th. - -- Henrik Olsen, Dawn Solutions I/S URL=http://www.iaeste.dk/~henrik/ "'Chapter Fifteen, Elementary Necromancy'", she read out loud. "'Lesson One: Correct Use of Shovel...'" Terry Pratchett, Jingo _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 26 Oct 2000 21:57:21 +0200 From: "george de fockert" [EMAIL PROTECTED] Subject: Mersenne: timing diffeence between win95 and linux Dear primers, This week I swapped my pentium [EMAIL PROTECTED] (2.5*75) for a pentium mmx 200@225 (3*75) To make sure that I did not overclock too much, I did run the torture test for some time under win95. Funny sideeffect : I could hear the program running because the on board switched power supply made a periodic high piched sound. When I did a time test for a 10M exponent it timed at 0.48, and a 6M at 0.28 A Pentium mmx @225 should be comparable to a pentium mmx @ 233 The gimps benchmark page lists a 10M exponent time for a P1mmx@233 at 0.637, and a 6M at 0.386. Somehow my pentium mmx is much too fast ! When running the same timing using linux mprime, I get a 10M time of 0.92, and a 6M time of 0.56. This is much too slow, and almost exactly a factor 2 slower as when using windows ! So, whats going on ? Anybody an explanation ? Something wrong with my system, or only the timer ? George de Fockert _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- End of Mersenne Digest V1 #787 **
Mersenne Digest V1 #779
Mersenne Digest Thursday, September 21 2000 Volume 01 : Number 779 -- Date: Mon, 18 Sep 2000 21:16:52 +0200 From: "Martijn Kruithof" [EMAIL PROTECTED] Subject: Re: Mersenne: primenet assignment question Hi, If you want double-checks, you can indicate this in the setup, go to the test/primenet menu, here you can indicate the type of work you want to do, this overrides the cpu setting. I can see that your exponent was reserved 2,4 days ago and expires in 85,6 days. After 88 days your exponent expires, unless you contact the primenet server earlier. In your case prime95 will try to connect to the primenet server after 28 days, then extending the exponent(s) you are working on. You can also do this manually when connected to the internet. (You can even indicate you want some 100 days by sending vacation information). You do not have to finish the assignment within the 88 days. Your reservation has to be extended before the exp column hits 0, and you could theoretically keep this assignment forever. Please do not start to format your text using outlook, many people will not be able to read your mails anymore. (You can try to put under Tools / options / Read / Fonts both the proportional and fixed font to courier new (font size smaller). And you will see be able to format using fixed fonts (and see the formatting others apply using a fixed font). This way the message is still sent unformatted as plain text.) Kind Regards, Martijn - - Original Message - From: "george de fockert" [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, September 18, 2000 7:46 PM Subject: Mersenne: primenet assignment question Dear primers, My 533 celeron which I configured for 4 hours/day has been given the following assignment (copied from status page and sorry for the formatting, anybody knows how to install a fixed font for outlook ?). prime fact current days exponentbits iteration run / to go / exp date updated date assigned computer ID Mhz Ver -- - - --- -- - -- --- --- 5627753 D* 63 37.8 -5.0 55.0 26-Aug-00 17:52 11-Aug-00 23:02 C274E1CE1 533 v19/v20 10356833 64 2.4 59.6 85.6 16-Sep-00 07:37 C274E1CE1 533 v19/v20 Why ? 533 * 4/24 is below 100MHz equivalent, so I expect doublechecks. Are all exponents doublechecked ? This assignment will keep it busy for more than half a year, so it will expire ! Even 4 hours is probably a too high estimate for my 'prime' computer time, because during scanning, all CPU time goes to waiting for my scanner, I hate polling drivers ! George de Fockert _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 18 Sep 2000 18:41:50 -0700 From: "Osher Doctorow" [EMAIL PROTECTED] Subject: Mersenne: Will the real operation please stand up? From: Osher Doctorow, Ph.D. [EMAIL PROTECTED], Mon. Sept. 18, 2000, 6:06PM In attempting to find a shorter proof of Fermat's Last Theorem (FLT) than the current one, I have become interested in the rather curious expressions g(x,y) = 1 - x + y and f(x,y) = x + y - xy. I have elsewhere indicated how an n-dimensional generalization of the real conjugate of one or both of these expressions would lead to a super-short proof of FLT - the real conjugate of g(x.y) is defined as 1 + x - y and the real conjugate of f(x,y) is defined as x + y -xy. Abstracts of 46 of my over 100 papers can be found on the internet at the Institute for Logic of the University of Vienna, http://www.logic.univie.ac.at, select ABSTRACT and then BY AUTHOR and then my name. However, I am here presenting a slightly different problem which is indirectly linked to Mersenne Primes via the Sophie Germain Prime - FLT - Fermat Number - Mersenne Number linkage. To shorten the presentation, I became curious about the expression (x - y)^^2 = x^^2 - 2xy + y^^2 and how it relates to f(x,y) = x + y - xy. Is it possible that either f(x,y) or f1(x,y) = x + y - 2xy is actually representable as a power of x - y? The answer seems to be no in the ordinary sense of power or exponent, but what about ordinals, cardinals, etc.? Is it possible that below the second power, there is a different infinite continuum of exponents from the familiar one? If so, then 2 would be the boundary between two continua, and this might explain its importance in FLT itself. Setting f(x,y
Mersenne Digest V1 #778
Mersenne Digest Monday, September 18 2000 Volume 01 : Number 778 -- Date: Thu, 14 Sep 2000 11:27:30 -0700 (PDT) From: John R Pierce [EMAIL PROTECTED] Subject: Re: Mersenne: Why do I get only double-checks I'm using a P3-500E box at college to run mprime. The relevant lines of the local.ini look like LastEndDatesSent=967023734 RollingStartTime=968950008 RollingAverage=4000 CPUType=1 CPUSpeed=500 CPUHours=24 How come I get given only double-checks to do? I don't mind too much -- the machine kills off a double-check in ten days -- but I'd be slightly surprised if the frontier of 'obsolete; use for double-checks only' had reached this one-year-old box yet. That Rolling Average figure looks kind of high, too. your rolling average of 4000 indicates your computer is 4 times slower than a 'typical' 500. Wierd tho, CPUType=1 ??!? s/b = 9 or 10 or something. - -jrp _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Fri, 15 Sep 2000 00:00:06 -0500 From: Ken Kriesel [EMAIL PROTECTED] Subject: Re: Mersenne: Why do I get only double-checks Setting CPU type in prime95 V20.4.1 and then examining local.ini, CPUType=3 is a Cyrix 6x86 CPUType=4 is a 486 CPUType=5 is a Pentium CPUType=6 is a Pentium Pro CPUType=7 is an AMD K6 CPUType=8 is a Celeron CPUType=9 is a PentiumII CPUType=10 is a PentiumIII CPUType=11 is an AMD Athlon So CPUType=1 must be what, an Intel 80286? (More likely an unsupported value.) If I enter CPUType=1 or 2 or 3, while editing local.ini, prime95 displays it as a Cyrix 6x86. RollingAverage=1000 means the system runs iterations at 1000/1000 the expected speed (indexed relative to George Woltman's PII-400 on a per-Megahertz basis) Lower RollingAverage numbers mean lower performance. Higher numbers, higher performance. Your P3-500 is performing much better than the lowly cpu type the program thinks it is. But it is given only double checks because the program thinks it's a much slower cpu type than it actually is, and so does the primenet server. Make the CPUType in local.ini match the actual processor type, and you can get first-time tests, and use code that's more efficient for your cpu because it's what George tuned for it. Options, CPU, click on Pentium III. Ken At 06:38 PM 9/14/2000 +0100, you wrote: I'm using a P3-500E box at college to run mprime. The relevant lines of the local.ini look like LastEndDatesSent=967023734 RollingStartTime=968950008 RollingAverage=4000 CPUType=1 CPUSpeed=500 CPUHours=24 How come I get given only double-checks to do? I don't mind too much -- the machine kills off a double-check in ten days -- but I'd be slightly surprised if the frontier of 'obsolete; use for double-checks only' had reached this one-year-old box yet. That Rolling Average figure looks kind of high, too. Tom _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sat, 16 Sep 2000 03:40:49 EDT From: [EMAIL PROTECTED] Subject: Mersenne: Re: A new series of Mersenne-like Gaussian primes On 07/09/2000 at 18:27:23 GMT [EMAIL PROTECTED] wrote: Dear Mike and others, This sequence is in actuality two sequences in one. The first are primes of the form 2^n - 2^[(n+1)/2] +1 and the other are primes of the form 2^n + 2^[(n+1)/2] +1, as you have delineated. I direct you to the following URL which is the home of the Sloane's On-Line Encyclopedia of Integer Sequences. http://www.research.att.com/~njas/sequences/ You will find the sequences as numbers A007670 A007671. Their addresses are: http://www.research.att.com/cgi-bin/access.cgi/as/njas/sequences/eisA.cgi?An um=A007670 http://www.research.att.com/cgi-bin/access.cgi/as/njas/sequences/eisA.cgi?An um=A007671 Hope you make use of this vital resource. Sincerely yours, Robert G. "Bob" Wilson v Ph.D. ATP / CFGI While happily acknowledging that the first 25 of these 33 (so far known) primes figure in that excellent database, I strongly dispute your assertion that "this sequence is in actuality two sequences in one". Why do you want to split the single series s[n] = (1+i)^n - 1 depending on whether n = 1 or 7 mod 8 (i.e. s[n] is in the right half of the complex plane) or not? Aurifeuille pointed out in 1873 [cf. Knuth, Vol. 2, p. 376] the identity 2^(4*m+2) + 1 = (2^(2*m+1) + 2^(m+1) + 1) * (2^(
Mersenne Digest V1 #777
Mersenne Digest Thursday, September 14 2000 Volume 01 : Number 777 -- Date: Sun, 10 Sep 2000 13:53:30 EDT From: "Chris Nash" [EMAIL PROTECTED] Subject: Re: Mersenne: Re: A new series of Mersenne-like Gaussian primes Hi Mike and Yann I don't have any Linux software. For searching for new primes of this series, the best program to use at present is PrimeForm/GW by Chris Nash. You could ask him ([EMAIL PROTECTED]) whether he has anything for Linux. Work is currently being done on a direct recompilation of PrimeForm/GW for Linux. Since PFGW is a command-line program, this should not be too difficult a task - in fact, PFGW is actually developed on BeOS using the GNU development tools and the Windows version is already a port. Peter Kosinar is currently looking at the rebuild, and in fact managed to get the BeOS objects to link first time on Linux. There were a few system-specific problems (for instance, none of the timing functions worked) and Peter has made a few changes, however, the resulting program failed. It seems this might be because of some differences between the versions of gcc used, the BeOS version is 2.9, and I've yet to get 2.95 to successfully build under BeOS. Peter now has all the source and is doing a full rebuild, I don't foresee any major problems, so a Linux version may be available very soon indeed. Best Wishes, and thanks for the recommendation! Chris _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 10 Sep 2000 12:25:06 -0700 From: Colin Percival [EMAIL PROTECTED] Subject: Re: Mersenne: Volunteers wanted At 7 Sep 2000 14:25:49 -, "Brian J. Beesley" [EMAIL PROTECTED] wrote: The problem could be a program bug (unlikely), an undiscovered bug in either Athlon or Pentium III floating-point arithmetic (again unlikely) or a random hardware glitch in either my system or the system against which I'm checking (much the most likely). Or we might just be unlucky. There are inputs for which the multiplication used in prime95 will not give the correct answer -- fortunately they are very rare and it is very unlikely that any would ever be encountered. (It isn't worth using safe multiplications because any problems will show up in the double check anyway.) I agree that a random hardware glitch is by far the most likely, but the possibility of unlucky values should be kept in mind. Colin Percival _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: 11 Sep 2000 00:31:05 -0400 From: "Robert Deininger" [EMAIL PROTECTED] Subject: Re: Mersenne: Volunteers wanted On Sun, Sep 10, 2000 3:25 PM, Colin Percival [EMAIL PROTECTED] wrote: Or we might just be unlucky. There are inputs for which the multiplication used in prime95 will not give the correct answer -- fortunately they are very rare and it is very unlikely that any would ever be encountered. (It isn't worth using safe multiplications because any problems will show up in the double check anyway.) This reminds me of something I've been meaning to ask about double checking. I looked at a bit of the database of double-checked exponents: ftp://mersenne.org/gimps/lucas_v.zip I noticed some exponents where the first-time and double-check results were submitted by the same person, using the same software, on the same machine. If there is a reproducible hardware problem, or one of these "bad" multiplications, then this double-check would not catch an error. Actually, I kind of doubt that the LL test was done twice. More likely one result was accidentally _submitted_ twice, and the friendly primenet server happily accepted both. (We know that the primenet server accepts results from people who do NOT have the exponents assigned to them.) Will these seemingly bogus double-checks be weeded out when the next synchronization is done? - --- Robert Deininger [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 11 Sep 2000 06:42:45 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Mersenne: Moriarty, where are you? Sorry to abuse the list, but Jean-Yves Canart obviously reads this list since he graciously replied to my recent request of volunteers. Unfortunately his address as given in the reply I received does not work. I'd be gratef
Mersenne Digest V1 #776
Mersenne Digest Sunday, September 10 2000 Volume 01 : Number 776 -- Date: Thu, 7 Sep 2000 02:19:55 EDT From: [EMAIL PROTECTED] Subject: Mersenne: Mersenne Primes Essay After a long and agonizing wait, I have finally received Official (TM) permission from the International Bacclaureate Organization to post my Mersenne Primes extended essay on the Internet. (Copyrights stink. Then again, they did give me an A.) Now that it's all legit, it's back on the Internet at http://homepages.go.com/~joekorovin/Mersenne.html (so the www.mersenne.org link isn't broken anymore, yay), and in a much nicer HTML form provided by Barry Brake. Things have changed since Nov. 1999; I no longer believe that there's a hidden Mersenne prime (although it was sure fun to suggest), but I still remain reasonably convinced about the validity of my conjecture. Stephan T. Lavavej _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 7 Sep 2000 14:25:49 - From: "Brian J. Beesley" [EMAIL PROTECTED] Subject: Mersenne: Volunteers wanted Hi guys, I've been assisting in quality assurance testing of Prime95 for some time and have had one of my systems run halfway through a LL test on a 10 million digit number. Unfortunately the intermediate result I have does not match the only other available value, which means that one of us is wrong. The problem could be a program bug (unlikely), an undiscovered bug in either Athlon or Pentium III floating-point arithmetic (again unlikely) or a random hardware glitch in either my system or the system against which I'm checking (much the most likely). To eliminate the first two possibilities it is neccessary to re-run the first half of the test. As I have savefiles at 1 million iteration intervals this could be done in parallel by 17 systems; I will be running (at least) one of these myself but would like to recruit 16 volunteers to check the remaining intervals. Volunteers should be running Prime95 or mprime v20.6 on an Intel Pentium II or PIII system. Please do not volunteer if you intend to run on an Athlon since this would make it impossible to determine if a processor bug is to blame. You will need to upload the save file, a binary file approximately 5 megabytes in size, from my ftp site, and unzip it; your segment of the work will take 13 CPU days (on a PII-400, according to George Woltman's benchmarks) with checkpoints at 1.3 day intervals. You should be prepared to check each checkpoint and report to me immediately should you find a discrepancy. I would like to finish the work as soon as reasonably possible, so reasonably fast systems are indicated - at least PII-400 running continuously. Unfortunately I cannot offer any recognition other than my personal thanks. (i.e. no CPU time credit, sorry!) If you're interested, please reply to me and I'll supply further instructions (how to download your specific file, precise details of how to set up the run and a list of my intermediate residuals at your checkpoints to compare with your values). Regards Brian Beesley _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 7 Sep 2000 09:27:31 -0500 From: "Steve" [EMAIL PROTECTED] Subject: Re: Mersenne: P-1 Credit I've found 2 factors so far during P-1 testing and received 0.001 years (about 8 or 9 hours) credit for each. Not much consolation as it 'cost' upwards of 100 P90 hours each to find them, but it beats getting no credit for spending the same amount of time not finding any. Steve "binarydigits" Harris [EMAIL PROTECTED] - -Original Message- From: Terry S. Arnold [EMAIL PROTECTED] To: [EMAIL PROTECTED] [EMAIL PROTECTED] Date: Thursday, September 07, 2000 1:46 AM Subject: Mersenne: P-1 Credit Does anyone have any skinny on when we will start getting credit for 1. doing P-1 testing? 2. finding a factor during P-1 testing? Terry Terry S. Arnold 2975 B Street San Diego, CA 92102 USA [EMAIL PROTECTED] (619) 235-8181 (voice) (619) 235-0016 (fax) _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 7 Sep 2000 20:47:03
Mersenne Digest V1 #775
Mersenne Digest Wednesday, September 6 2000 Volume 01 : Number 775 -- Date: Sun, 03 Sep 2000 15:11:23 +0200 From: Yann Forget [EMAIL PROTECTED] Subject: Mersenne: Re: A new series of Mersenne-like Gaussian primes Hi, From: [EMAIL PROTECTED] In 1969 I investigated the series of complex (Gaussian) integers: s[n] = (1+i)^n - 1. [skip] I hereby solicit the aid of those in GIMPS et al. to extend this series of primes! Do you have a program, preferably in C, which would work on Linux ? Yann _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 04 Sep 2000 16:34:26 +0200 From: Paul Landon [EMAIL PROTECTED] Subject: Re: Mersenne: smallest possible factor There is a simple proof without using quadratic thingies. The prime f divides a^(f-1)-1 /* Fermat's Little Theorem */ It may first divide a Mersenne number with a smaller exponent, call it a^E-1 and then all exponents that are multiples of E, one of which equals f-1, let's call it EK = f-1. (f-1) is even, call it 2kE. So for E to be odd and f | a^E-1 then f=2kE+1. Indeed all the powers of 2 that are factors of f-1 must "drop", so f=(2^m)kE+1 for all odd E and all bases that f doesn't divide. Similarly for Fermat divisors, all the other factors of f-1 must "drop" leaving only powers of 2. In base 2 using quadratic residues (whatever they are :-) gives us the 1 or 7 mod 8 for divisors of 2^p-1. Does anyone have any (more) heuristics for the probabilistic distribution of K or 2^m.k, where E=(f-1)/K ?? My shot in the dark is that it is less likely for an f=1 (mod 8) to "drop" 3 powers of 2 and divide 2^E-1 with an odd exponent, E than it would be for another f=7 (mod 8) to "drop" only one. Pröst, Paul Landon From: Alexander Kruppa Subject: Re: Mersenne: smallest possible factor Spike Jones wrote: A few weeks ago, I thought someone posted something like: 2^n-1 where n is prime cannot have any factor smaller than n. Did I get that right? Is there a simple proof? spike Factors of a mersenne number Mp are always of the form f=2*p*k+1, k may be as small as 1. The proof that factors are 2kp+1 is not simple as far as I remember and uses the theory of quadratic residues (and thus I didn't understand it). See it on Chris Caldwells (superb) page on Prime numbers, http://www.utm.edu/research/primes/ . The proof is at http://www.utm.edu/research/primes/notes/proofs/MerDiv.html Ciao, Alex. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Tue, 5 Sep 2000 02:27:05 EDT From: [EMAIL PROTECTED] Subject: Mersenne: Assembly optimization I found this while browsing mindlessly: http://www.agner.org/assem/pentopt.htm Rather interesting, if you ask me. I don't know whether it makes me want to learn assembler or run like hell in the other direction. I seem to gather that black magic is taught on that page, which might be useful in optimizing Prime95. (I'll go back to the safe, safe world of C, where I can just type "gcc -s -O3 - -mcpu=i686 -fomit-frame-pointer -ffast-math -funroll-loops -malign-double - -fstrict-aliasing -o foo.exe foo.c" to make everything all right. :- ) Stephan "NOP" Lavavej _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Tue, 5 Sep 2000 00:03:53 -0700 From: "John R Pierce" [EMAIL PROTECTED] Subject: Re: Mersenne: Assembly optimization I found this while browsing mindlessly: http://www.agner.org/assem/pentopt.htm Rather interesting, if you ask me. I don't know whether it makes me want to learn assembler or run like hell in the other direction. I seem to gather that black magic is taught on that page, which might be useful in optimizing Prime95. prime95 is already HEAVILY optimized even beyond what that page describes. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Wed, 06 Sep 2000 22:53:17 -0700 From: "Terry S. Arnold" [EMAIL PROTECTED] Subject: Mersenne: P-1 Credit Does anyone have any skinny on when we will start getting credit for 1. doing P-1 testing? 2. finding a factor during P-1 testing? Terry Terry S. Arnold 2975 B S
Mersenne Digest V1 #774
Mersenne Digest Saturday, September 2 2000 Volume 01 : Number 774 -- Date: Thu, 31 Aug 2000 03:41:17 -0400 From: Matt Gauthier [EMAIL PROTECTED] Subject: Mersenne: Re: Mersenne Digest V1 #773 In message [EMAIL PROTECTED], Mersenne Digest writes: Do not "make clean" in linux/, this will remove all the FFT object files! Only remove prime.o, primenet.o and menu.o . Also, the GIANTS.H file is all uppercase in the zip file so case-sensitive unix does not find it. Rename it to giants.h . The latest version of gas can, apparantly, handle intel syntax with the appropriate psuedo-op. I haven't looked into it, but it should be possible to get prime95 to compile on any i386 unix box with trivial changes once the new version is the standard. - -- Matt Gauthier [EMAIL PROTECTED] _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Sun, 03 Sep 2000 16:07:40 +0200 From: Yann Forget [EMAIL PROTECTED] Subject: Mersenne: Re: Glucas beta version released. Hi, I'll test it on RS6000: IBM B50, PPC 604e, 375 Mhz, 500 Mo RAM Any input about possible optimization welcomed. Best regards, Yann -- Date: Thu, 31 Aug 2000 07:58:23 +0200 From: Guillermo Ballester Valor [EMAIL PROTECTED] Subject: Mersenne: Glucas beta version released. After a long and hot summer, I've finally written a first beta version of Glucas. This is a C-program to make L-L test. Still, there is no good scripts to make the binaries in a easy way. I need the help of testers to make fast binaries and fix possible bugs. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 31 Aug 2000 11:59:10 + From: Alexander Kruppa [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Mersenne Digest V1 #773 Matt Gauthier wrote: In message [EMAIL PROTECTED], Mersenne Digest writes: Do not "make clean" in linux/, this will remove all the FFT object files! Only The latest version of gas can, apparantly, handle intel syntax with the appropriate psuedo-op. I haven't looked into it, but it should be possible to get prime95 to compile on any i386 unix box with trivial changes once the new version is the standard. At last, writing assembler in old gas syntax was a nightmare. The readily available nasm likes Intel syntax, too, and most programming-inclined x86-unix boxes will have it installed, so we could use that too to assemble the FFT sources. But assembling is not really necessary to build the mprime binary even after a "make clean" because the elf .o files can be converted from the intel .obj file which are also in the linux/ directory. This takes binutils which like coff-i386 object files (see the linux/makefile) and many linux boxes are not configured that way - you'd have to rebuild your binutils first. So, yes you can make clean and still make the binary if you have a suitably configured system. But unless one is working on the FFT code, one might just keep the .o files and not worry about all this... Ciao, Alex. _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 31 Aug 2000 08:38:11 -0500 (EST) From: [EMAIL PROTECTED] Subject: Mersenne: Check This Out! Just got a new email at THEMAIL.COM - --___TheMail_56_Boundary___ Content-type: text/plain Dear [EMAIL PROTECTED], qing he wanted us to inform you that THEMAIL.COM is now giving out a powerful free email service. Best of all, I get paid for reading email! - Check it out for yourself at: http://www.themail.com/ref.htm?ref=1243269 TheMail.com PostMaster - --___TheMail_56_Boundary___-- _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Thu, 31 Aug 2000 20:17:26 +0200 From: Guillermo Ballester Valor [EMAIL PROTECTED] Subject: Re: Mersenne: Re: Glucas beta version released. Hi: Yann Forget wrote: Hi, I'll test it on RS6000: IBM B50, PPC 604e, 375 Mhz, 500 Mo RAM The first bug has already found by Yann Forget!. It will affect to those users of GNU gcc compiler other than x86 platform, gcc will give an error. You can try now the version 1.99 with the first stupid bug fixed. The new source code: ftp://209.133.33.182/pub/valor/Glucas-1
Mersenne Digest V1 #773
Mersenne Digest Wednesday, August 30 2000 Volume 01 : Number 773 -- Date: Mon, 28 Aug 2000 13:29:24 +0100 From: gordon spence Subject: Mersenne: Credits per FFT Size Marc Getty wondered previously How does the CPU time contributed get calculated? I would assume that there is a standard credit for each FFT size, but I can't find what that credit is anywhere on mersenne.org. Can anyone help fill in the following? Taking the data from the status page on mersenne.org where it gives timings per fft size per iteration, taking the mid-point exponent for each fft size and then multiplying by the 5.5 conversion factor that George quotes gives the following FFTExponent Credit (P90 years) 160 2972750 0.043 192 3612500 0.062 224 4266500 0.089 256 4924000 0.113 320 5882500 0.177 384 7122500 0.262 448 8375000 0.368 512 967 0.474 640 115750000.751 768 14051.110 896 16561.548 1024191250002.001 1280228650003.094 1536277150004.515 179232606.328 2048376750008.056 25604507500012.861 3072546518.967 3584642026.648 4096741533.675 And yes there are a few of us using fft's in excess of 1792, like up in the 4096 range.so when my exponent gets done in 2004 I should get about 36 years of credit in one hit G regards G _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 28 Aug 2000 16:38:30 +0100 From: "Andy" Subject: Mersenne: Tips on compiling source I'm trying to compile the source code for Prime95 for a wintel machine and am slightly lost for how to do so. I have Visual C++, gcc, a86 and just about everything else. My background is Java development (3 1/2 years) so I am not used to header files and assembly language. Though do know the fundamentals. Any help would be great. Also any programming tutorials etc (online or hard copy) on assembler would be great. Andy _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 28 Aug 2000 11:56:27 -0500 From: (Mikus Grinbergs) Subject: Re: Mersenne: Credits per FFT Size On Mon, 28 Aug 2000 13:29:24 +0100 gordon spence wrote: Taking the data from the status page on mersenne.org where it gives timings per fft size per iteration, taking the mid-point exponent for each fft size and then multiplying by the 5.5 conversion factor that George quotes gives the following FFTExponent Credit (P90 years) 256 4924000 0.113 320 5882500 0.177 Interesting data. I'm running a K6-III-400, whose other chief CPU-burners are a software MIDI synth and an occasional compile, and which is halted from time to time for software installs. Upon exponents LESS than the mid-point, my measured elapsed time was 0.057 years and 0.088 years, respectively. I see my K6-III-400 is TWICE as fast as the reference P90 !!! mikus _ Unsubscribe list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt -- Date: Mon, 28 Aug 2000 11:16:47 -0700 From: Eric Hahn Subject: Re: Mersenne: CPU Time Credit Calculation Marc Getty wrote: How does the CPU time contributed get calculated? I would assume that there is a standard credit for each FFT size, but I can't find what that credit is anywhere on mersenne.org. Actually, the formula isn't based on FFT size. To get a good estimate of how much time you'll get credited for any given exponent, you'll need to multiply the exponent minus 1 by the average time it takes to do each iteration. Then multiply by the number of times faster the PC is than a P-90. Finally the % of a year you get is the approx. amount of time credited. For example: On the exponent 5,593,943... Multiply 5,593,942 by .275 to get 1,538,334 seconds. Multiply 1,538,334 by 3.5 (for a PII-266) to get 5,384,169 secs. 5,384,169 seconds is 17.073% of a year... So you'll get approx 0.171 P-90 years credit I doubt that anyone out there is using more then a 1792 K FFT. Well There are actually a few of us brave souls out there who are QA'ing exponents in FFT sizes all the way up to 4096K!! Based on my estimates, the exponent I'm QA'ing will provide me with ~36.348 P-90 years of credit when comple
