Re: Mersenne: All Cunningham Wanted Numbers Factored
[EMAIL PROTECTED] wrote: > > Hi, > > > > FWIW if you have a dual CPU system (mine is running 2 * PIII-850 > on a Supermicro P6DBE m/b), running ECM on small exponents > on one processor makes an ideal foil to running LL tests on the > other. Ditto on my dual PIII-1GHz. > The ECM process uses so little memory that it runs > practically in the L2 cache, except during Stage 2. The LL test will > slow down a bit during ECM stage 2, but that's only about 30% of > the time - And the slow-down is not very significant--seems to be less than 10%. > whereas running LL tests on both processors can slow > both processes down quite substantially due to the loading on the > memory bus. Definitely. About 30% on each processor here. Meaning I used to have about 1.4 processor-equivalents when both were doing LL. Now I have close to 1.0 doing LL and another 1.0 helping to find factors. Seems better overall. Perhaps a Mersenne number I would have got will be shown to be prime. So be it. It is a thrill to be able to contribute to this effort. Gerry -- mailto:[EMAIL PROTECTED] Gerry Snyder, AIS Symposium Chair, Region 15 RVP Member San Fernando Valley, Southern California Iris Societies in warm, winterless Los Angeles--USDA 9b-ish, Sunset 18-19 my work: helping generate data for: http://galileo.jpl.nasa.gov/ _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Prime Net Server
Is there scheduled maint. going on with the server today, or is this a unscheduled outage? Matt
Re: Mersenne: All Cunningham Wanted Numbers Factored
Hi, Coincidentally to Peter's message, and as an encouragement to anyone else working in this field, it just so happens that one of my systems discovered a previously unknown (AFAIK) factor of one of the Cunningham Project numbers yesterday evening: [Fri Sep 07 21:33:06 2001] ECM found a factor in curve #199, stage #2 Sigma=6849154397631118, B1=300, B2=3. UID: beejaybee/Simon2, P1136 has a factor: 9168689293924594269435012699390053650369 Factors this size aren't too easy to find, but (despite the subject line in Peter's message) there are still a large number of candidates which need work done on them. FWIW if you have a dual CPU system (mine is running 2 * PIII-850 on a Supermicro P6DBE m/b), running ECM on small exponents on one processor makes an ideal foil to running LL tests on the other. The ECM process uses so little memory that it runs practically in the L2 cache, except during Stage 2. The LL test will slow down a bit during ECM stage 2, but that's only about 30% of the time - whereas running LL tests on both processors can slow both processes down quite substantially due to the loading on the memory bus. BTW this was found with Prime95 v21.2, so I guess that's another check mark on the QA table: ECM _does_ find factors! Regards Brian Beesley _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
