Re: Mersenne: Prime64?
On Sat, 17 Jun 2000 [EMAIL PROTECTED] wrote: > Will Prime95 be rewritten to run on the Itanium, when it comes out? Seems to > me like 64-bit operation will speed it up significantly, as will the insane > amount of registers and floating point units and all the other > microprocessor > whatnot that I'm not current on. Intel has had documentation available on the Web for a while that details the architecture of Itanium. If Prime95 is ever rewritten for IA64 it would have to be not only a total rewrite but a complete rethinking of the FFTs it uses. For example, integer multiply-adds take only a little longer than floating point multiply-adds; should IA64Prime use an integer or floating point FFT? If integer, there are big delays in shuffling between integer and FPU registers (only the FPU can multiply). If floating point, loads and stores will all take longer, the cache behavior is totally different, and the arrays involved get longer because you can't pack bits as densely as an integer solution. Itanium can do two FPU operations per clock, but both can be multiply-adds instead of just multiplies or adds. Can you rearrange a real-valued FFT to use multiply-adds as much as possible? It could cut the operation count in half if you do, but to my knowledge no one has yet done so. It's been done for complex FFTs, but Prime95 really wants real-valued FFTs, not complex ones. Moving to IA64 will be a much bigger challenge than simply rewriting half a meg of assembly language. jasonp _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Linux And The Slippery Gnome
TeamG: Trying to start a PrimeHunt on a Linux box, but can't find the Gnome switch/requeste(o)r to get the screen resolution down enough so I can read without a microscope. Can anyone help? Am running Redhat 6.1 with a VooDoo 3500 GFX card. So until last year I thought Linux was a cartoon character. Leave and learn.. Best Wishes, Stefanovic _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: Mersenne Digest V1 #748
Williamette is the next-generation x86 architecture machine. It has (will have) a way accelerated CPU clock and even more instructions execute in fewer clocks, but it has a deeper pipeline and increased instruction latency. First generation Williamettes are supposedly going to debut around 1.2GHz and go up from there. It also has more and better onchip cache, both L1 and L2. I believe it has some major structural changes to the PPro/P2/P3 style bus, requiring completely new chipsets. -jrp - Original Message - From: <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, June 17, 2000 6:56 PM Subject: Mersenne: Re: Mersenne Digest V1 #748 > <> > > Remind me what a Willamette is again. All I know about are Merced (I mean, > Itanium), and the second-generation Itanium called McKinley. > > STL > _ > 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
Mersenne: Prime64?
Will Prime95 be rewritten to run on the Itanium, when it comes out? Seems to me like 64-bit operation will speed it up significantly, as will the insane amount of registers and floating point units and all the other microprocessor whatnot that I'm not current on. A review (thanks, Stefan Struiker!) of the Itanium mentions, "The CPU will then switch to 32-bit mode on the fly and carry on as if it were a more powerful PIII or Willamette. This all happens because the Itanium supports the IA-32 instructions natively All software has to be rewritten to take advantage of the IA-64 architecture." So Prime95 will run on an Itanium, but a "Prime64" might be even better and wickedly faster. With what I'm learning about programming, it seems that more registers are always a good thing, especially for memory-intensive processes. STL _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Re: Mersenne Digest V1 #748
<> Remind me what a Willamette is again. All I know about are Merced (I mean, Itanium), and the second-generation Itanium called McKinley. STL _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Factoring Assignments: Are They Always "First-Time?"
Jeff Woods wrote: >>being found. Currently, all exponents thru Prime95's limit of >>79.3M have been factored to at least 2^50... If a factor is >>found for an exponent, it's eliminated from further testing >>of any kind. > >Isn't the factor itself verified? Yes, it is. However, at least in the case of Prime95, George has written the code such that the factor is validated before it's even displayed as a being a factor and written to the results file. If it's invalid, the code continues as if the "factor" was never found... Eric _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Pointers on farming
On Sat, 17 Jun 2000, Michael Bell wrote: > Warning on K6's: As far as GIMPS is concerned they're not too good, because > the FPU is about half the speed of the Intel Pentium FPU. (If you run RC5 > then they're as good, if not better, because they have very good integer > units). K6 is not good at RC5 either; see http://www.pcbenchmarks.com/distribu.htm I've heard that RC5 requires some kind of rotate function that is hardwired on Intel processors but not on K6 and Alpha. _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: LOST NUMBERS
On Sat, 17 Jun 2000 17:28:52 +0200 (CEST), Henrik Olsen wrote: >On Sat, 17 Jun 2000, Lem Novantotto wrote: >> On Sat, 17 Jun 2000 05:37:06 -0400, in Mersenne_mailing_list you >> wrote: >> >Is all your hard work(and subsequent credit) lost? No, although the server >> >has already re-assigned them to another account it will still accept the >> >results and properly credit your account for the completed work. >> Hi! >> I think it would be nice to post the mersenne numbers you're still >> working to, and that have been reassigned, so, hopefully, the new >> tester can read them and stop his testing. Otherwise HE is going to >> loose time and credit. >Since first and double checks are credited equally(as far as I know), >both should get credited with the same amount of work except for counting >tests. >Time spent on a doublecheck is only wasted if it's turned into a >triplecheck and all three results agree. > Yes, but they are testing in the 10-million-digit range, so it is not only a question of time and credit. I think it would be just fair to inform the new testers that they are doing in fact just a doublecheck and let them decide if they want to continue under these circumstances or take another 'fresh' exponent. Siegmar _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: Pointers on farming
Michael Bell wrote: > ...back to your 37pence/MHz figure. Also note memory prices have gone up, so > 32M now costs about £40-50!! Maybe this is the first time in recent history > the price of a computer has stabilised?? Hmm, dont think so. I was over at Fry's electronics this morning. The 400 MHz machines like the one I paid 2400 bucks for less than 2 yrs ago with the same amount of memory was selling for 300 bucks. Which I think is about 200 pounds? The 2000-2300 dollar machines are all 1 Ghz now. Computer prices look to me to be as much in freefall as ever. spike _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: LOST NUMBERS
On Sat, 17 Jun 2000 17:28:52 +0200 (CEST), in Mersenne_mailing_list you wrote: >On Sat, 17 Jun 2000, Lem Novantotto wrote: >> Hi! >> I think it would be nice to post the mersenne numbers you're still >> working to, and that have been reassigned, so, hopefully, the new >> tester can read them and stop his testing. Otherwise HE is going to >> loose time and credit. >Since first and double checks are credited equally(as far as I know), >both should get credited with the same amount of work except for counting >tests. Yes. But I'm saying is that, in my experience, if you send a LL_first_checking result after someone else, your test isn't considered a double checking... astonishing enough, it isn't considered at all. Otherwise, how do you explain what happened to me? See my post in reply to: Mersenne: assignment 'stolen' a few posts ago. -- Bye. Lem -- 'CLOCK is what you make of it' -- _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Factoring Assignments: Are They Always "First-Time?"
>From: Jeff Woods <[EMAIL PROTECTED]> >To: [EMAIL PROTECTED] >Subject: Re: Mersenne: Factoring Assignments: Are They Always >"First-Time?" >Date: Sat, 17 Jun 2000 17:14:00 -0400 > >At 01:00 PM 6/17/00 -0700, you wrote: (snip) >>If a factor is >>found for an exponent, it's eliminated from further testing >>of any kind. > >Isn't the factor itself verified? I would assume it is, however verifying a factor takes well under a P-90 second. 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
Mersenne Digest V1 #748
Mersenne DigestSaturday, June 17 2000Volume 01 : Number 748 -- Date: Thu, 15 Jun 2000 22:59:27 +0200 From: "Martijn Kruithof" <[EMAIL PROTECTED]> Subject: Re: Mersenne: Assignment "stolen" Hi, It is a first time test, I do not care to run some double checks, the problem however is that I cannot even put double-check in the worktodo file, the assignment will be deleted as soon as the primenet server is contacted. It says it already has a result for the exponent. I think I will back the files up and make it a double-check assignment after the next database sync. (Well before the values are assigned again by primenet.) When an unassigned exponent gets reported PrimeNet will assign it to the one reporting to work on the exponent. Anybody knows when the next database sync will be? Kind Regards, Martijn - - Original Message - From: "Brian J. Beesley" <[EMAIL PROTECTED]> To: "Martijn" <[EMAIL PROTECTED]> Sent: Thursday, June 15, 2000 9:12 PM Subject: Re: Mersenne: Assignment "stolen" > On 15 Jun 00, at 17:31, Martijn wrote: > > > I just saw that an exponent I am testing (due in about > > 20 days) sudennly was removed from my account report. > > When looking in the cleared exponents list, "my" > > exponent is listed as cleared by milbournea (no > > offence). Should I stop testing this exponent or should > > I still await the final result and return it (i.e. > > making a double-check unnecessary / let it be the > > double check.) > > I take it you had a first-test assignment. > > If so I'd let it complete. This will be accepted by PrimeNet & will > eventually save someone else running a double-check. > > If, however, your assignment was a double-check, there seems little > point in continuing :( > > > When returning, will the LL time be credited? > > I don't think so. If this really worries you then stop the program & > mail me the Pnnn file (will shrink by a useful amount if you > compress it using zip or tar z) & I'll finish the run off for you. > Then delete the offending line from worktodo.ini & restart the > program. > > > Regards > Brian Beesley > _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 15 Jun 2000 18:55:52 -0400 From: George Woltman <[EMAIL PROTECTED]> Subject: Re: Mersenne: Assignment "stolen" Hi Martijn, At 10:59 PM 6/15/00 +0200, Martijn Kruithof wrote: >the problem however is >that I cannot even put double-check in the worktodo file, the >assignment will be deleted as soon as the primenet server is >contacted. If you leave your worktodo.ini file alone, everything will be OK. That is, your worktodo.ini should read "Test=exponent,64,1" The server will accept your result but probably will not give you CPU credit. There is no difference between a double-check and a first-time test!! Prime95 merely lowers your probability of finding a Mersenne prime if it is told this is a double-check. Other than that, the Lucas-Lehmer test is the same. If you have any further questions, just email me. Regards, George _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 15 Jun 2000 22:11:58 +0200 From: Lem Novantotto <[EMAIL PROTECTED]> Subject: Re: Mersenne: Assignment "stolen" On Thu, 15 Jun 2000 17:31:48 +0200, in Mersenne_mailing_list you wrote: >I just saw that an exponent I am testing (due in about >20 days) sudennly was removed from my account report. >When looking in the cleared exponents list, "my" >exponent is listed as cleared by milbournea (no >offence). Should I stop testing this exponent or should >I still await the final result and return it (i.e. >making a double-check unnecessary / let it be the >double check.) >When returning, will the LL time be credited? Hi! Almost the same thing happened to me some months ago. 5 days before sending the result of a LL test, everything was fine. When I sent the result, I got an error saying that the exponent wasn't assigned to me (an then no credit... which made change my account, to see if something had gone wrong with it). But some days after, answering my question, Primenet folks told me that the exponent had been reassigned to me after 60 days of no communication from the previous tester: but he had sent the result just before me, so the exponent was considered cleared. But why my test wasn't seen as a double checking, then? I dunno'. - -- Bye. Lem - -- 'CLOCK is what you make of it' -- _ Unsubscribe & list info -- http://www.scruz.net/~luke/sign
Re: Mersenne: Factoring Assignments: Are They Always "First-Time?"
At 01:00 PM 6/17/00 -0700, you wrote: >being found. Currently, all exponents thru Prime95's limit of >79.3M have been factored to at least 2^50... If a factor is >found for an exponent, it's eliminated from further testing >of any kind. Isn't the factor itself verified? _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Factoring Assignments: Are They Always "First-Time?"
Stefan Struiker wrote: >When a requested factoring assignment is listed with, say, 52 in >an account log, does this mean it has been factored to 52 bits, >but _without_ success? Or could a factor have already been >found in some cases, but less than 52 bits long? If it's listed as 52 in the fact-bits column of the report, it means that it's been trial-factored thru 2^52 without any factors being found. Currently, all exponents thru Prime95's limit of 79.3M have been factored to at least 2^50... If a factor is found for an exponent, it's eliminated from further testing of any kind. Eric _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Factoring Assignments: Are They Always "First-Time?"
TeamG: When a requested factoring assignment is listed with, say, 52 in an account log, does this mean it has been factored to 52 bits, but _without_ success? Or could a factor have already been found in some cases, but less than 52 bits long? My strategy in factoring 13.3 mill exponents and up, is to save L-L testing and DCing time by knocking some out early. Seem to be on a roll, too, with factors found 40% of the time, with a turnaround of 40 hours per. Tell me I'm not just a Foole For Factores, "Donne, Anne Donne, Undone," Stefanovic _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: Pointers on farming
> >Here is a calculation I did about six months ago > >AMD K6/2 500 MHz (plus fan)45 pounds Sterling >Super-socket-7 motherboard 45 pounds >32M 100Mhz RAM 20 pounds >Old 486 to put it in1 pound > >To this one should add the cost of electricity. The computer draws about >40 Watts. A Watt costs about 0.60 pounds per year. For, say, three years >of computation, add > >120 Watt-years of electricity 72 pounds > -- >Total 183 pounds > >That's 36.6 pence per MHz; or, since I am writing it off after three >years, 0.389 pence per trillion cycles. > Warning on K6's: As far as GIMPS is concerned they're not too good, because the FPU is about half the speed of the Intel Pentium FPU. (If you run RC5 then they're as good, if not better, because they have very good integer units). This means that on GIMPS effectively you get 250MHz, so you get 73.2 pence per MHz. So providing you can find an AT form factor PII/Socket 370 Motherboard (which I managed to do last December), you can put a Celeron in instead, although a 500MHz Celeron costs about £85 instead of 45, you get back to your 37pence/MHz figure. Also note memory prices have gone up, so 32M now costs about £40-50!! Maybe this is the first time in recent history the price of a computer has stabilised?? Michael Bell. _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: LOST NUMBERS
On Sat, 17 Jun 2000, Lem Novantotto wrote: > On Sat, 17 Jun 2000 05:37:06 -0400, in Mersenne_mailing_list you > wrote: > >Is all your hard work(and subsequent credit) lost? No, although the server > >has already re-assigned them to another account it will still accept the > >results and properly credit your account for the completed work. > > Hi! > I think it would be nice to post the mersenne numbers you're still > working to, and that have been reassigned, so, hopefully, the new > tester can read them and stop his testing. Otherwise HE is going to > loose time and credit. Since first and double checks are credited equally(as far as I know), both should get credited with the same amount of work except for counting tests. Time spent on a doublecheck is only wasted if it's turned into a triplecheck and all three results agree. -- Henrik Olsen, Dawn Solutions I/S URL=http://www.iaeste.dk/~henrik/ ZOOLOGY, n. The science and history of the animal kingdom, including its king, the House Fly (Musca maledicta).The Devil's Dictionary, Ambrose Bierce. _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: Pointers on farming
Steinar H. Gunderson <[EMAIL PROTECTED]> writes >>2. Which type of processor, memory etc will give the most bang for the buck? >> We rarely see anything beyond P2-250's, so I would have to pay retail for >>that. > Here is a calculation I did about six months ago AMD K6/2 500 MHz (plus fan)45 pounds Sterling Super-socket-7 motherboard 45 pounds 32M 100Mhz RAM 20 pounds Old 486 to put it in1 pound To this one should add the cost of electricity. The computer draws about 40 Watts. A Watt costs about 0.60 pounds per year. For, say, three years of computation, add 120 Watt-years of electricity 72 pounds -- Total 183 pounds That's 36.6 pence per MHz; or, since I am writing it off after three years, 0.389 pence per trillion cycles. -- Tony _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: LOST NUMBERS
On Sat, 17 Jun 2000 05:37:06 -0400, in Mersenne_mailing_list you wrote: >Is all your hard work(and subsequent credit) lost? No, although the server >has already re-assigned them to another account it will still accept the >results and properly credit your account for the completed work. Hi! I think it would be nice to post the mersenne numbers you're still working to, and that have been reassigned, so, hopefully, the new tester can read them and stop his testing. Otherwise HE is going to loose time and credit. -- Bye. Lem -- 'CLOCK is what you make of it' -- _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: LOST NUMBERS
Hi ALL: This is a letter I sent asking what happened to the prime numbers I was working on. I am posting it here to remind people who are doing 10million digit numbers to log on at least once a month to update there page so this doesn't happen to them Hi Lawrence, I reviewed the server logs regarding these exponents and what has happened is the timeout period(60 days) that the server will wait prior to releasing them had expired. This is tied to your contacting the server so that Prime95 can update the expected completion date, you missed the window by 3 days. Is all your hard work(and subsequent credit) lost? No, although the server has already re-assigned them to another account it will still accept the results and properly credit your account for the completed work. Regards, Brad Bernard PrimeNet Support Engineer -Original Message- From: Lawrence Murray [mailto:[EMAIL PROTECTED]] Sent: Friday, June 16, 2000 5:15 AM To: [EMAIL PROTECTED] Subject: not assigned Hi my name is Lawrence Murray and I have been running 2 10million numbers since september of last year 33220001 & 33219313 one is 49% done and the other is 63% done. when I went to upload the latest results it said that these numbers are not assigned to me I would like to know why they were taken away from me. My duel pentium 600mhz processor computer have been working on these numbers and nothing else for 9 months and I am not willing to loose the credit for all that work my computers have put into this. could you please straighten this out right away thank you LP Murray _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
