Mersenne Digest Friday, May 19 2000 Volume 01 : Number 737 ---------------------------------------------------------------------- Date: Wed, 17 May 2000 11:30:40 +0200 (MET DST) From: "Benny.VanHoudt" <[EMAIL PROTECTED]> Subject: Re: Mersenne: error > On 17 May 00, at 9:57, Benny.VanHoudt wrote: > > > I've been using prime95 since sept. 1998 and never had any problems. > > Until yesterday I was testing an exponent in the 9.5 - 10 million > > range, but suddenly an error appeared while contacting the Primenet > > server (the exponent was almost finished +98%). > > > > I got the commen windows 95 error message: This program has performed > > an illegal operation and will be shut down. > > Are you using HTTP or RPC to communicate with the PrimeNet server? If > you're using RPC, try changing to HTTP. If you have a local proxy > configured, make sure it's still operational. > > The other thing you could try is restoring the two .dll files which > should be in the Prime95 directory; download a fresh copy of > prime95.zip (from my server > ftp://lettuce.edsc.ulst.ac.uk/gimps/software/prime95.zip > if entropia.com is still being uncooperative) & extract them. Or > simply restore the files from a backup. That's what I did and the previous problem disappeared. The result is that prime95 is working again but was unable to use the files with the intermediate results. As a result it's starting all over again. It took my PC more than two months to get to the current point, and the exponent would have expired on the 19th of may. Any suggestions ? Benny > > Regards > Brian Beesley - ------------------------------------------------------------------- Benny Van Houdt, University of Antwerp Dept. Math. and Computer Science PATS - Performance Analysis of Telecommunication Systems Research Group Universiteitsplein, 1 B-2610 Antwerp Belgium email: [EMAIL PROTECTED] - -------------------------------------------------------------------- _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 11:10:40 -0000 From: "Brian J. Beesley" <[EMAIL PROTECTED]> Subject: Re: Mersenne: error On 17 May 00, at 11:30, Benny.VanHoudt wrote: > > That's what I did and the previous problem disappeared. The > result is that prime95 is working again but was unable to > use the files with the intermediate results. As a result it's > starting all over again. It took my PC more than two months > to get to the current point, and the exponent would have expired > on the 19th of may. Dou you still have the old savefiles and the worktodo.ini file? If they are in the same directory as Prime95 then it should just continue from wherever it was at when the last savefile was written. You could try renaming the Pnnnnnnn file to something else, then renaming Qnnnnnnn to Pnnnnnnn, this will fix any problem due to the Pnnnnnnn file being corrupt. (Where nnnnnnn is the exponent) If you're still out of luck, but have the files you think are neccessary, get back to me & I'll take a look at them for you. Regards Brian Beesley _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 13:40:22 +0200 From: [EMAIL PROTECTED] Subject: Mersenne: Prime95 and boot At 02:32 PM 5/10/00 +0200, Yann Forget wrote: >The new version of Prime95 pop up >every time Windows is restarted. >So the users of my network don't >like it any more. :-( >Is that could be changed ? I have the same behavior with version 19.1. It seems that it appears when prime95 is set to run as a Windows 95/98 Service AND when there's no more work to do (yellow color). Didier. Didier BOIVIN GAMBRO - Hospal Industrie MEYZIEU FRANCE tél : +33 4 72 45 25 07 fax : +33 4 72 45 25 19 e-mail : [EMAIL PROTECTED] ** Disclaimer from Gambro Corporation ** Privileged/confidential information may be contained in this message. If you are not the addressee indicated in this message (or responsible for the delivery of the message to such person), you may not copy or deliver this message to anyone. In such case, you should destroy this message and kindly notify the sender by reply e-mail. Please advise immediately if you or your employer does not consent to Internet e-mail for messages of this kind. Opinions, conclusions and other information in this message that pertain to the sender's employer and its products and services represent the opinion of the sender and do not necessarily represent or reflect the views and opinions of the employer. ** End of disclaimer ** _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 19:47:38 +0200 From: Henk Stokhorst <[EMAIL PROTECTED]> Subject: Mersenne: time needed for factoring L.S., Just curious, what makes factoring 13.388.659 take four times as long as 13.375.793? YotN, Henk Stokhorst _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 12:55:04 -0700 From: Eric Hahn <[EMAIL PROTECTED]> Subject: Re: Mersenne: time needed for factoring Henk Stokhorst wrote: >L.S., > >Just curious, what makes factoring 13.388.659 take four times as >long as 13.375.793? It's because 13,388,659 is past the cutoff of 13,380,000 where Prime95 starts factoring to the depth of 2^65 instead of 2^64. Normally, increasing the depth by a factor of one only doubles the time required. However, because of the nature of chip architecture, it takes a longer period of time than normal above 2^62 and again above 2^64 to do the necessary calculations (more instructions and such). Eric _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 15:57:01 EDT From: "Nathan Russell" <[EMAIL PROTECTED]> Subject: Re: Mersenne: time needed for factoring >From: Henk Stokhorst <[EMAIL PROTECTED]> >To: [EMAIL PROTECTED] >Subject: Mersenne: time needed for factoring >Date: Wed, 17 May 2000 19:47:38 +0200 > >L.S., > >Just curious, what makes factoring 13.388.659 take four times as long as >13.375.793? > >YotN, > >Henk Stokhorst Hmm... Maybe this should be a FAQ question. I sincerely doubt you'll be the last one to ask it in the next month or two. Exponents beyond 13,380,000 are trial-factored to 65 bits rather than 64 bits. This means that the program needs to check (almost) twice as many factors; additionally, sieving each of the potential factors takes longer for hardware-related reasons that appear in the list archives a week or two back, IIRC. Regards Nathan Russell ________________________________________________________________________ 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: Wed, 17 May 2000 16:57:14 -0400 From: Bruce A Metcalf <[EMAIL PROTECTED]> Subject: Re: Mersenne: error At 09:57 AM 5/17/00 +0200, Benny.VanHoudt wrote: >I've been using prime95 since sept. 1998 and never had any problems. >Until yesterday I was testing an exponent in the 9.5 - 10 million >range, but suddenly an error appeared while contacting the Primenet >server (the exponent was almost finished +98%). > >I got the commen windows 95 error message: This program has performed >an illegal operation and will be shut down. I had a similar incident this past week running Prime95 version 20.4.1 under Windoze95 testing in the 4.7M range. Since it *is* a Windoze machine, I first tried just rebooting, only to get the same failure immediately upon Prime95 starting. I then reinstalled Prime95 from the download zip file and have been running fine since. No corruption of the data files were observed, and no reptition of the crash has yet occurred. I wasn't going to offer it as a bug report until it happened again, but it looks like I'm not alone. If there is any data I could collect on the occasion of another crash that could help analysis of the bug, please let me know and I'll try to secure and report same. Bruce A. Metcalf mailto:[EMAIL PROTECTED] http://myweb.magicnet.net/bmetcalf _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 22:19:49 +0100 From: "Peter Owen" <[EMAIL PROTECTED]> Subject: Mersenne: Primenet Error 2250 Is there a problem with the PrimeNet Server? I keep getting the following message when prime95 tries to contact the server. Contacting PrimeNet Server. ERROR 2250: Server unavailable The FAQ at http://www.entropia.com/ips/faq.html may have more information. The FAQ says that this is caused by using the RPC protocol in certain circumstances - but I am using the HTTP protocol! Peter _________________________________ Peter Owen 11 The Downs Blundellsands Road West Liverpool L23 6XS UK mailto:[EMAIL PROTECTED] _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 15:37:15 -0600 From: "Aaron Blosser" <[EMAIL PROTECTED]> Subject: RE: Mersenne: time needed for factoring >Henk Stokhorst wrote: >>L.S., >> >>Just curious, what makes factoring 13.388.659 take four times as >>long as 13.375.793? > >It's because 13,388,659 is past the cutoff of 13,380,000 where >Prime95 starts factoring to the depth of 2^65 instead of 2^64. >Normally, increasing the depth by a factor of one only doubles >the time required. However, because of the nature of chip architecture, it >takes a longer period of time than normal >above 2^62 and again above 2^64 to do the necessary >calculations (more instructions and such). Now, I may be totally off base here, but... The reason is because the integer part of the Intel CPU is 64 bit...okay, so Prime95 does some additional steps to provide greater bit depth factoring... Now, if that's really the case, would it be of any advantage to have the FPU handle factoring? I know that some processors only do factoring because they have a slow FPU to begin with (like Cyrix and AMD K6 chips), but would a Pentium be able to use it's FPU to do trial-factoring to greater bit depths any faster than the software based solution George uses beyond 64 bits? Just curious... Better yet, do any of the wacky SIMD/MMX/3DNow instructions provide any possible benefits for trial factoring? I recall a discussion before about how those instructions wouldn't be too useful for LL testing because of they only handle double-word sized data (32 bits), but for trial-factoring...any uses? Aaron _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 17:20:26 -0700 From: Stefan Struiker <[EMAIL PROTECTED]> Subject: Mersenne: OT But Of Interest: [Info-IA64] Latest Update] This is a multi-part message in MIME format. - --------------E3856447CD619503209DCA52 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit - --------------E3856447CD619503209DCA52 Content-Type: message/rfc822 Content-Transfer-Encoding: 7bit Content-Disposition: inline Received: from panoramix.valinux.com (panoramix.valinux.com [198.186.202.147]) by emu.prod.itd.earthlink.net (8.9.3/8.9.3) with ESMTP id RAA16006; Wed, 17 May 2000 17:08:25 -0700 (PDT) Received: from localhost ([127.0.0.1] helo=panoramix.valinux.com) by panoramix.valinux.com with esmtp (Exim 3.03 #1 (Debian)) id 12sDlG-0007n8-00; Wed, 17 May 2000 17:01:58 -0700 Received: from nat-su-33.valinux.com ([198.186.202.33] helo=mail.valinux.com) by panoramix.valinux.com with esmtp (Exim 3.03 #1 (Debian)) id 12sDUd-0007jy-00 for <[EMAIL PROTECTED]>; Wed, 17 May 2000 16:44:47 -0700 Received: from esindelar-laptop.su.valinux.com ([10.1.2.106] helo=valinux.com) by mail.valinux.com with esmtp (Exim 2.12 #6) id 12sDUd-00068q-00 for [EMAIL PROTECTED]; Wed, 17 May 2000 16:44:47 -0700 Message-ID: <[EMAIL PROTECTED]> Date: Wed, 17 May 2000 16:47:10 -0700 From: Eric Sindelar <[EMAIL PROTECTED]> Organization: VA Linux Systems X-Mailer: Mozilla 4.61 [en] (X11; I; Linux 2.2.13 i686) X-Accept-Language: en MIME-Version: 1.0 To: [EMAIL PROTECTED] Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: [Info-IA64] Latest Update Sender: [EMAIL PROTECTED] Errors-To: [EMAIL PROTECTED] X-Mailman-Version: 1.1 Precedence: bulk List-Id: News, press releases, and announcements for the Trillian Linux/IA64 project (read only, no posts) <info-ia64.lists.linuxia64.org> X-BeenThere: [EMAIL PROTECTED] X-Mozilla-Status2: 00000000 In case you haven't already heard.... On Monday 5/15, SGI released their IA-64 Linux compiler to the open source community. In addition, today, Red Hat released their first IA-64 Linux distribution to developers. Go to http://www.ia64linux.org to get the links to these releases! - - The IA-64 Linux Webmaster _______________________________________________ Info-IA64 maillist - [EMAIL PROTECTED] http://lists.linuxia64.org/lists/listinfo/info-ia64 - --------------E3856447CD619503209DCA52-- _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 21:07:37 EDT From: [EMAIL PROTECTED] Subject: Mersenne: Where's the script? A while ago we were discussing about a Java / JavaScript thing to put on the Mersenne page. I'm wondering if it's up yet, and if so, where it is. Also, I'm wondering if anyone can tell me how many digit's a certain exponent has. Thanks! Mark _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 19:24:17 -0700 From: Eric Hahn <[EMAIL PROTECTED]> Subject: RE: Mersenne: time needed for factoring Aaron Blosser wrote: >>Henk Stokhorst wrote: >>>L.S., >>> >>>Just curious, what makes factoring 13.388.659 take four times as >>>long as 13.375.793? >> >>It's because 13,388,659 is past the cutoff of 13,380,000 where >>Prime95 starts factoring to the depth of 2^65 instead of 2^64. >>Normally, increasing the depth by a factor of one only doubles >>the time required. However, because of the nature of chip >>architecture, it >>takes a longer period of time than normal >>above 2^62 and again above 2^64 to do the necessary >>calculations (more instructions and such). > >Now, I may be totally off base here, but... > >The reason is because the integer part of the Intel CPU is 64 >bit...okay, so Prime95 does some additional steps to provide >greater bit depth factoring... > >Now, if that's really the case, would it be of any advantage >to have the FPU handle factoring? I know that some processors >only do factoring because they have a slow FPU to begin with >(like Cyrix and AMD K6 chips), but would a Pentium be able to >use it's FPU to do trial-factoring to greater bit depths any >faster than the software based solution George uses beyond 64 >bits? Actually, George uses the FPU for trial-factoring. The problem is that even the FPU is only 80 bits (IEEE standard). Factors up to 2^64 can get the results in one stage (64-bits), however you have to take extra steps to get any additional bits above that up to 2^76 where Prime95's limit is (64-bits + 12-bits) This means it takes one stage to get the first 64 bits of a result and another stage to get the remaining bits.... >Better yet, do any of the wacky SIMD/MMX/3DNow instructions >provide any possible benefits for trial factoring? I recall a >discussion before about how those instructions wouldn't be too >useful for LL testing because of they only handle double-word >sized data (32 bits), but for trial-factoring...any uses? Personally, I doubt it would benefit any, but I could be wrong... Eric _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 19:24:10 -0700 From: Eric Hahn <[EMAIL PROTECTED]> Subject: Re: Mersenne: Where's the script? Mark wrote: >A while ago we were discussing about a Java / JavaScript thing >to put on the Mersenne page. I'm wondering if it's up yet, and >if so, where it is. Yes, it is up. George modified a javascript module I wrote and put it into the benchmark page at the following address: http://www.mersenne.org/bench.htm It calculates the *estimated* time to perform a L-L test based on CPU Type/Speed/Hours and the exponent... >Also, I'm wondering if anyone can tell me >how many digit's a certain exponent has. >Thanks! Divide the exponent by 3.32192809488 and round DOWN to the nearest whole integer to get the number of digits... Eric _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 17 May 2000 21:27:06 -0500 From: "Levi Broderick" <[EMAIL PROTECTED]> Subject: Re: Mersenne: Where's the script? > I'm wondering if anyone can tell me how many digit's a certain exponent has. Assuming the exponents are in the form 2^x, we can use logs. (Everybody remember the log song from the Ren & Stimpy show?) The exponent 2^x must be converted to 10^y, and y will be the number of digits in the decimal representation of the number. To convert x to y, multiply x by log 2, or divide by 3.32192. Take for example, 15000. You'll end up getting 2^15000 = 10^(15000/3.32192) = 10^4515.4609. Thus, the number has 4,515 (chop off the decimal) digits. ~ Levi _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 18 May 2000 03:27:43 EDT From: [EMAIL PROTECTED] Subject: Re: Mersenne: Where's the script? D you think we can add this to the script? a little thing saying exponent, has x digits. All you have to do ( according to everyone) is multiply the exponent by log 2, and round up. It seems like a good idea to me. Anyone else? _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 18 May 2000 07:41:20 -0000 From: "Brian J. Beesley" <[EMAIL PROTECTED]> Subject: Re: Mersenne: error On 17 May 00, at 16:57, Bruce A Metcalf wrote: > I had a similar incident this past week running Prime95 version 20.4.1 > under Windoze95 testing in the 4.7M range. Since it *is* a Windoze > machine, I first tried just rebooting, only to get the same failure > immediately upon Prime95 starting. > > I then reinstalled Prime95 from the download zip file and have been running > fine since. No corruption of the data files were observed, and no > reptition of the crash has yet occurred. If there's a sudden burst of these incidents, maybe something external is to blame. Maybe a virus infecting Prime95 or one of the DLLs it uses; could also be something hitting the comms routines in Windows. It's perhaps not coincidental that the PrimeNet server seems to have been having problems recently. Benny says (private communication) that the refreshed program found both his savefiles corrupt, so he's had to restart :( Perhaps this is a good time to suggest: (a) running a periodic backup job including the files in your Prime95 directory, so that you have something fairly recent to fall back on in the event of disaster; (b) adding a line "InterimFiles=1000000" to prime.ini, then exit & restart Prime95/NTPrime. With v19.2 and v20.x, this will cause an extra save file to be written every 1000000 iterations, this extra save file will be kept indefinitely & is therefore useful as a fallback. Also valuable if you run into hardware reliability problems e.g. a failed cooling fan. Note 1, you can change the value 1000000 if you wish. Note 2, to get rid of surplus save files you have to delete them manually. > > If there is any data I could collect on the occasion of another crash that > could help analysis of the bug, please let me know and I'll try to secure > and report same. > At least write down everything in the error box. Don't rely exclusively on e.g. screen capture software, which may not function correctly on a system which is in some sort of distress. 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, 18 May 2000 04:57:56 -0700 From: Stefan Struiker <[EMAIL PROTECTED]> Subject: Mersenne: Benchmarks For "Factoring Only" TeamM: Benchmarx for L-L testing now are legion (love that Athlon 700 overclocked to 1000! ). But how do the machines stack up in straight-shot factoring? Can we draw any reliable conclusions from the published L-L numbers? O Server Speak To Me Again Tomorrow... Best Regards, Stefanovic _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 18 May 2000 14:16:35 -0700 From: Russel Brooks <[EMAIL PROTECTED]> Subject: Re: Mersenne: Primenet Error 2250 I saw it too a couple of days ago but it was gone when I tried again a couple of hours later. cheers... Russ Peter Owen wrote: > Is there a problem with the PrimeNet Server? I keep getting the following > message when prime95 tries to contact the server. > > Contacting PrimeNet Server. > ERROR 2250: Server unavailable > The FAQ at http://www.entropia.com/ips/faq.html may have more information. > > The FAQ says that this is caused by using the RPC protocol in certain > circumstances - but I am using the HTTP protocol! _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 18 May 2000 17:50:23 -0400 From: "St. Dee" <[EMAIL PROTECTED]> Subject: Re: Mersenne: Primenet Error 2250 At 14:16 05/18/2000 -0700, Russel Brooks wrote: > >Peter Owen wrote: >> Is there a problem with the PrimeNet Server? I keep getting the following >> message when prime95 tries to contact the server. >> >> Contacting PrimeNet Server. >> ERROR 2250: Server unavailable >> The FAQ at http://www.entropia.com/ips/faq.html may have more information. >> >> The FAQ says that this is caused by using the RPC protocol in certain >> circumstances - but I am using the HTTP protocol! > >I saw it too a couple of days ago but it was gone when I tried again a >couple of hours later. > >cheers... Russ I saw it happening earlier today. The server seems to be going through some periodic difficulties. K _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 19 May 2000 22:47:38 -0400 From: George Woltman <[EMAIL PROTECTED]> Subject: Mersenne: M#36 & M#37 Hi all, Congratulations to all GIMPS members on achieving another milestone! Today, double-checking has proved that M(2976221) and M(3021377) are the 36th and 37th Mersenne primes. Keep up the good work! George _________________________________________________________________ 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 #737 ******************************
