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 FFT Exponent 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 9670000 0.474 640 11575000 0.751 768 14050000 1.110 896 16560000 1.548 1024 19125000 2.001 1280 22865000 3.094 1536 27715000 4.515 1792 32600000 6.328 2048 37675000 8.056 2560 45075000 12.861 3072 54650000 18.967 3584 64200000 26.648 4096 74150000 33.675 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 > > FFT Exponent 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 completed. Eric _________________________________________________________________________ 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 23:16:34 +0200 From: "Steinar H. Gunderson" Subject: Mersenne: Re: Tips on compiling source On Mon, Aug 28, 2000 at 04:38:30PM +0100, Andy wrote: >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. You're aware you need NASM as well? That's at least the problem I faced when I tried to compile it myself. There should be reasonable object files included that you can link to, though... /* 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: Tue, 29 Aug 2000 09:03:37 +0200 From: Henk Stokhorst Subject: Mersenne: Prime95 and Pentium III 1.13 GHz Hi, for all of you who couldn't get their 1.13 GHz Pentiums working correctly with Prime95, there is a story on that at http://www.tomshardware.com/cpu/00q3/000801/pentiumiii-01.html 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, 29 Aug 2000 14:20:12 +0000 From: Alexander Kruppa Subject: Re: Mersenne: Tips on compiling source Andy wrote: > 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. The Linux version should compile without too much hassle, but you have to remove the calls to the SEC5 function from the code, or put a security.h file in the source base directory in which you #define SEC5(a,b,c) 0L In fact, this might be done automatically in the makefile, you can replace [ ! -e ../security.h ] && touch ../security.h || true by [ ! -e ../security.h ] && echo "#define SEC5(a,b,c) 0L" >../security.h || true (George, can this go the the makefile in source.zip ?) 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 . I've been experimenting with the ECM code for a while now, trying to add something to allow B2>2^32 and maybe computing the group order, so I've compiled the source rather a lot recently. If you have any specific questions, feel welcome to ask me, maybe I've run into the same problems, too. Btw, I have never tried to compile the windows version, but the documentation of the source mentions that this might be difficult to do. 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, 29 Aug 2000 10:15:16 -0400 From: Jeff Woods Subject: Re: Mersenne: Prime95 and Pentium III 1.13 GHz Intel issued a RECALL of *all* 1.13GHz Pentium 3's yesterday: http://news.cnet.com/news/0-1003-200-2634198.html At 09:03 AM 8/29/00 +0200, you wrote: >Hi, > >for all of you who couldn't get their 1.13 GHz Pentiums working >correctly with Prime95, there is a story on that at > >http://www.tomshardware.com/cpu/00q3/000801/pentiumiii-01.html > >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 _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt ------------------------------ Date: Tue, 29 Aug 2000 23:19:55 -0700 From: Spike Jones Subject: Mersenne: smallest possible factor 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 _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt ------------------------------ Date: Wed, 30 Aug 2000 12:03:41 +0000 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: Thu, 31 Aug 2000 07:58:23 +0200 From: Guillermo Ballester Valor Subject: Mersenne: Glucas beta version released. Hi to all: 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. Obviously, for intel platforms, his 'big brother' mprime is faster. In alphas is about as fast as Mlucas. I don't know how well (or bad) it runs other machines, I'm waiting your news ;-). To see how you can help, and read first: ftp://209.133.33.182/pub/valor/README.htm to see more details from Glucas: ftp://209.133.33.182/pub/valor/README.Glucas.htm To download the source: ftp://209.133.33.182/pub/valor/Glucas-1.98.tar.gz Thanks to Ernst Mayer for all his help, specially for the use of his server. Regards Guillermo. _________________________________________________________________________ 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 #773 ******************************
