Mersenne Digest Friday, May 26 2000 Volume 01 : Number 740 ---------------------------------------------------------------------- Date: Wed, 24 May 2000 11:51:52 -0500 From: [EMAIL PROTECTED] (Mikus Grinbergs) Subject: Re: Mersenne: The recent popularity of Single-Checking > There is a user, "_______", who has almost 100 single-checkingassignments > out on a single machine ID. These would take a state-of-the-art box well > over two years to finish. Additionally, these assignments have almost > identical figures for time to complete etc. The first exponent in this > group is _______; the others are directly below it. Since when has this project become a competitive event ? This mailing list has gotten several messages like the one above, which I interpret as comparing ANOTHER USER to standards set by the writer, rather than acknowledging that *all* users are contributors to the project. Will it mean the end of the world if that other user had mis-stated the resources available to him ? I think it is intrusive to publicly comment about ANOTHER USER when the writer spots something that does not meet his own expectations. Can't we please let each participant remain responsible for his own performance? "Why do you look down on your brother? For we will all stand before God's judgment seat." (Romans 14:10) mikus _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 24 May 2000 11:54:04 -0700 From: Eric Hahn <[EMAIL PROTECTED]> Subject: Re: Mersenne: The recent popularity of Single-Checking Nathan Russell wrote: >There is a user, "sd70045", who has almost 100 single-checking >assignments out on a single machine ID. These would take a >state-of-the-art box well over two years to finish. Additionally, >these assignments have almost identical figures for time to >complete etc. The first exponent in this group is 8936071; the >others are directly below it. I examined this, and found out that there is actually 197 assignments checked out to this individual (188 to the same machine ID (7 dbl-chks, 5 factoring, 176 L-L tests)). By my estimates, this single machine ID has >5 yrs worth of work for even the faster state-of-the-art PC. While they have various run times, they all have 16 days to go and 16 days until expiration... They all were also updated on the same date and time (10-Feb-00 17:55). None appear to have had any work performed on them at all!! While I normally might think this might be a person switching over to use PrimeNet from previously not using it, and possibly using a large cluster (using the same ID for the entire cluster), there are a few indications this isn't the case. First, their ranking on PrimeNet is 8112 and 2323 for primality testing and factoring respectively, and their P-90 CPU hrs/day at 13.79. Second, their ranking on George's list is 6800 (with only one additional exponent tested above PrimeNet's count). Finally, they have 6 other machines that actually appear to be performing some kind of work. In any case, these exponents will expire in 16 days. As a result, I'm not concerned about it. Within 3 weeks they'll be re-circulated among other users. The only thing that would cause concern, is if the user intentionally updates these exponents in the next two weeks... Eric _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 24 May 2000 20:29:30 +0100 (BST) From: Chris Jefferson <[EMAIL PROTECTED]> Subject: Re: Mersenne: The recent popularity of Single-Checking > Nathan Russell wrote: > >There is a user, "sd70045", who has almost 100 single-checking > >assignments out on a single machine ID.... .... > > In any case, these exponents will expire in 16 days. As a > result, I'm not concerned about it. Within 3 weeks > they'll be re-circulated among other users. The only thing > that would cause concern, is if the user intentionally updates > these exponents in the next two weeks... > xactly! Last time I checked there was an infinate number of possible mersenne candidates and using the current version of prime95/NT/whatever, we are umlikely to run out any time soon,so unless things get REALLY serious, surely with things like this it's best to just wait till they expire and let the automatted system deal with it? Chris > > Eric > > > _________________________________________________________________ > 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, 24 May 2000 21:32:22 EDT From: "Nathan Russell" <[EMAIL PROTECTED]> Subject: Re: Mersenne: The recent popularity of Single-Checking >Since when has this project become a competitive event ? > >This mailing list has gotten several messages like the one above, >which I interpret as comparing ANOTHER USER to standards set by >the writer, rather than acknowledging that *all* users are >contributors to the project. Will it mean the end of the world >if that other user had mis-stated the resources available to him ? No, however it reduces the chances of finding a prime for others and delays the milestones. I am not in the project solely to find a prime - I have already committed to spending this entire summer from late June to early September on a single exponent for QA, reducing my chance of finding a prime at least eightfold for that time. >I think it is intrusive to publicly comment about ANOTHER USER when >the writer spots something that does not meet his own expectations. >Can't we please let each participant remain responsible for his own >performance? "Why do you look down on your brother? For we will >all stand before God's judgment seat." (Romans 14:10) > >mikus I just have a problem with extreme cases like this one. It's one thing to cache three months of work, and quite another to cache the better part of a decade. Also, many of the exponents in question were down in the 8.1 M range, implying that the user had deliberately taken on smaller reissued exponents and abandoned them. This hurts the progress of GIMPS as a whole. Not that I have not myself abandoned exponents - my machine dropped several double-checks when I stopped running 24/7 due to problems sleeping. Nathan ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 25 May 2000 15:42:51 EDT From: "Nathan Russell" <[EMAIL PROTECTED]> Subject: Mersenne: Error I just got this in an ECM run on M(10079). What does it mean? Is something wrong with my machine? [Thu May 25 15:00:24 2000] ECM found a factor in curve #263, stage #2 Sigma=1155032128984, B1=250000, B2=25000000. ERROR: Factor doesn't divide N! Nathan ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 25 May 2000 14:10:27 -0700 From: Eric Hahn <[EMAIL PROTECTED]> Subject: Mersenne: Mersenne P-1 Database Calling all P-1 factorers, I'm in the process of creating a database of P-1 factoring data for all Mersenne numbers. I have not found any other database for this information available on the 'net. There is some data kept by Will that's available, but it only goes to M(169,991)... I am collecting data for unfactored Mersennes presently, but this may expand -- depending on size of the database -- to include all Mersenne numbers not completely factored... If you're interested in seeing this database get started, and of making use of it, please send me your data. I need the exponent, B1 bound, and B2 bound. You can send the a results file if that's the easiest... Eric _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 00:50:06 +0100 From: "Ian L McLoughlin" <[EMAIL PROTECTED]> Subject: Mersenne: errors Hi, I appear to be getting error messages of 'input equalling output' every 4 or so days... O.K. its only a Cyrix 333...does this invalidate results? Should I switch to SETI? :) Regards, Ian (U.K.) BTW it took me 9 months to do 9763841 LL!!! _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 25 May 2000 19:45:50 -0600 From: "Aaron Blosser" <[EMAIL PROTECTED]> Subject: RE: Mersenne: errors >O.K. its only a Cyrix 333...does this invalidate results? >Should I switch to SETI? :) >BTW it took me 9 months to do 9763841 LL!!! The Cyrix probably has the worst FPU of any x86 clone... I had a Cyrix 300 running and I quickly realized that it's good for factoring and that was about it. I've also got a couple AMD K6 400's that are similarly pokey. They could do a double-check of around M(5M) in reasonable time, but I put them on factoring because that's just what those processors can best be doing. Now...my Pentium III 600's are kicking butt at LL testing... It's all a matter of finding the right work for the CPU you have. If all you can do is factoring with a certain system, hey, factoring is fun too! Aaron _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 25 May 2000 20:36:21 -0700 From: Stefan Struiker <[EMAIL PROTECTED]> Subject: Mersenne: A Curiosity: Lower Clocks And A Penchant For 500ms Disking To All: I'm running a 533MHz Celeron in a low-end eMachines box, DCing a 53xxyyy-exponent Mersenne candidate. By using the utilities RCache and PV2000, I can knock the number of clocks/iter below 82,300,000. When I achieve this minor miracle, however, the disk light begins to pulse about twice per second -- dot dot dah for any Morsies out there. Can anyone explain this? Loving The Lower Numbers, But Spooked By The Light, Stefanovic _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 25 May 2000 23:44:22 -0400 From: "Vincent J. Mooney Jr." <[EMAIL PROTECTED]> Subject: Re: Mersenne: The recent popularity of Single-Checking Cheers to you Mikus. I second you wholeheartedly. At 11:51 AM 5/24/00 -0500, Mikus Grinbergs wrote: ....... some snipping ........ > >Since when has this project become a competitive event ? > >This mailing list has gotten several messages like the one above, >which I interpret as comparing ANOTHER USER to standards set by >the writer, rather than acknowledging that *all* users are >contributors to the project. Will it mean the end of the world >if that other user had mis-stated the resources available to him ? > >I think it is intrusive to publicly comment about ANOTHER USER when >the writer spots something that does not meet his own expectations. >Can't we please let each participant remain responsible for his own >performance? _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 25 May 2000 23:39:47 -0500 From: Ken Kriesel <[EMAIL PROTECTED]> Subject: Re: Mersenne: Error I saw something similar once, out of hundreds of ECM curves that I've run. It happened on the curve being run while I adjusted memory limits on the program (Version 20.4.1, April 25 file date), if I recall correctly. Ken At 03:42 PM 5/25/2000 EDT, you wrote: >I just got this in an ECM run on M(10079). What does it mean? Is something >wrong with my machine? > >[Thu May 25 15:00:24 2000] >ECM found a factor in curve #263, stage #2 >Sigma=1155032128984, B1=250000, B2=25000000. >ERROR: Factor doesn't divide N! > >Nathan _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 09:33:28 -0000 From: "Brian J. Beesley" <[EMAIL PROTECTED]> Subject: Re: Mersenne: Error On 25 May 00, at 23:39, Ken Kriesel wrote: > I saw something similar once, out of hundreds of ECM curves > that I've run. > It happened on the curve being run while I adjusted memory limits > on the program (Version 20.4.1, April 25 file date), if I recall correctly. There was a problem with some versions which resulted in this error message appearing constantly. I think the problem was related to a factor which was already known being found again - this happens constantly but should be resolved by reference to the low?.txt file. > >[Thu May 25 15:00:24 2000] > >ECM found a factor in curve #263, stage #2 > >Sigma=1155032128984, B1=250000, B2=25000000. > >ERROR: Factor doesn't divide N! Suggest you ensure that you're running v20.4 & that your lowm.txt file is up-to-date & not corrupt. Sometimes you can get extra carriage returns in the file as a consequence of the way in which it's downloaded. Otherwise it's one for George. BTW from George's ECM status pages it seems that either factors have become _very_ hard to find recently. Anyone have any views on this? 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, 26 May 2000 11:16:08 +0100 From: Michael Oates <[EMAIL PROTECTED]> Subject: Re: Mersenne: Error Brian, >BTW from George's ECM status pages it seems that either factors have >become _very_ hard to find recently. Anyone have any views on this? If you are referring to the normal factoring that Prime95 does, I am still getting them, I have also noticed a tendency to get quite a few '2 in a row' by that I mean if I get a factor, the next number is often a factor, far more than you would expect by chance, is there a reason for this ? My account name is 'MOates' if you want to check. PS. I am not a mathematician! Regards, Mike, - -- ATLAS CELESTE - Bevis Star Atlas - & "The CD-ROM" http://www.u-net.com/ph/mas/bevis/ Astronomy in the UK http://www.u-net.com/ph/ _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 09:21:03 -0400 From: "keith" <[EMAIL PROTECTED]> Subject: Mersenne: memory limits do the memory limits actually help it at all? it used to be set at like 10 MB or whatever, so i moved it up to 200, and i havnt noticed a performance gain whatsoever. Also it doesn't even seem to be utilizing more RAM, because the system monitor shows what it always has. Anyone got a clue whats going on? I have 256MB ram, athlon 850. Thanks _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 15:48:16 +0000 From: Alexander Kruppa <[EMAIL PROTECTED]> Subject: Re: Mersenne: Error "Brian J. Beesley" wrote: > On 25 May 00, at 23:39, Ken Kriesel wrote: > > > I saw something similar once, out of hundreds of ECM curves > > that I've run. > > It happened on the curve being run while I adjusted memory limits > > on the program (Version 20.4.1, April 25 file date), if I recall correctly. > > There was a problem with some versions which resulted in this error > message appearing constantly. I think the problem was related to a > factor which was already known being found again - this happens > constantly but should be resolved by reference to the low?.txt file. I got the same error in a F14 curve (I jumped out of my seat). George told me that it was a bug in v20.1 where the GCD routine sometimes returned bogus factors, which were then trapped in a sanity check. That error was fixed in 20.3 . I dont know about errors by faulty low[mp].txt files, but that sure was not the reason in my case, as F14 has no known factors and the error occurred only once out of hundreds of curves. > > >[Thu May 25 15:00:24 2000] > > >ECM found a factor in curve #263, stage #2 > > >Sigma=1155032128984, B1=250000, B2=25000000. > > >ERROR: Factor doesn't divide N! > > Suggest you ensure that you're running v20.4 & that your lowm.txt > file is up-to-date & not corrupt. Sometimes you can get extra > > BTW from George's ECM status pages it seems that either factors have > become _very_ hard to find recently. Anyone have any views on this? I think the 2^p+1 list still offers a few good candidates. There have been much fewer curves run on them than on their "2 less" counterparts. I'm focusing on F14 right now, while Richard Crandall's challenge still is on, but predictably, nothing much happened so far. Ciao, Alex. _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 10:37:48 EDT From: "Nathan Russell" <[EMAIL PROTECTED]> Subject: Mersenne: Errors Hi everyone, George contacted me and stated that he was unable to recreate the error and suspects that it was a one-time fluke; he wants me to let him know if it recurs. This is the first error I have had on the machine, so I am not concerned. Thanks to all who gave advice. Nathan P.S. I was in the wrong on the "recent popularity" issue. My intent was to notify the list about a possible error that was taking place in the reservation of exponents, not to insult the individual user. I appologize if that was not the impression that I gave. ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 11:24:27 EDT From: "Nathan Russell" <[EMAIL PROTECTED]> Subject: Re: Mersenne: Error >"Brian J. Beesley" wrote: > > There was a problem with some versions which resulted in this error > > message appearing constantly. I think the problem was related to a > > factor which was already known being found again - this happens > > constantly but should be resolved by reference to the low?.txt file. I am running v20.4.1, so I suspect I'm okay in that regard. >I got the same error in a F14 curve (I jumped out of my seat). George told me >that it >was a bug in v20.1 where the GCD routine sometimes returned bogus factors, >which >were then trapped in a sanity check. That error was fixed in 20.3 . I dont >know >about >errors by faulty low[mp].txt files, but that sure was not the reason in my >case, >as F14 has >no known factors and the error occurred only once out of hundreds of >curves. The exponent that I was running also has no known factors. > > BTW from George's ECM status pages it seems that either factors have > > become _very_ hard to find recently. Anyone have any views on this? > >I think the 2^p+1 list still offers a few good candidates. There have been >much >fewer curves >run on them than on their "2 less" counterparts. >I'm focusing on F14 right now, while Richard Crandall's challenge still is >on, >but predictably, >nothing much happened so far. > >Ciao, > Alex. I deliberately run ECM on exponents that 1) are relatively large and do not appear to be "immortal". For example, I wouldn't devote a large chuck of time to, say, M727, which has occupied the "hot seat" since I have joined GIMPS. I wonder how long it's been there... - -or- 2) have had much less ECM run than their immediate neighbors. Examples would be M751 and F13. I have 250 curves on M751 queued to run, simply because I feel that the larger thrill connected with cracking such a nearly "immortal" exponent is worth the reduced chance, and because that exponent is currently less factored than its neighbors, making this a good opportunity to run a low unfactored exponent. Nathan ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 18:58:15 +0200 From: Martijn <[EMAIL PROTECTED]> Subject: Re: Mersenne: memory limits keith wrote: > > do the memory limits actually help it at all? > it used to be set at like 10 MB or whatever, so i moved it up to 200, and i > havnt noticed a performance gain whatsoever. Also it doesn't even seem to > be utilizing more RAM, because the system monitor shows what it always has. > Anyone got a clue whats going on? I have 256MB ram, athlon 850. Thanks > The memory setting is only relevant for P-1 factoring, not for LL-testing or classical factoring. Kind Regards, Martijn - -- http://jkf.penguinpowered.com Linux distributies voor maar Fl 10 per CD, inclusief verzendkosten! _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 13:35:23 EDT From: "Nathan Russell" <[EMAIL PROTECTED]> Subject: Re: Mersenne: memory limits >The memory setting is only relevant for P-1 factoring, not for >LL-testing or >classical factoring. > >Kind Regards, Martijn It should probably be added that additional memory actually only makes P-1 go to higher bounds, thereby increasing the chance of avoiding an LL test. It will do little or nothing to help the per-iteration time AFAIK; in fact, if you run P-1 to higher bounds, it will likely take longer. I could be wrong on this... Nathan ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 26 May 2000 17:15:32 -0300 (EST) From: Enio Schutt Junior <[EMAIL PROTECTED]> Subject: Mersenne: which O.S. Hi, I have both Linux and Windows installed in my machine, I know that Linux is more reliable, uses the hardware better, and so on... Well, this may be just theoretical details... When running prime95 in linux, is there some real overall advantage, even small (not only in speed) ? Regards, Enio _________________________________________________________________ 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 #740 ******************************
