>Depends on the speed of the machine(s) you are using. Look at the >benchmark info at www.mersenne.org, or let me know your speed and >machine type and I will check it for you.
>Best Wishes, >Stefanovic >It is a matter of personal preference. You can figure out how long >a double-check would take at http://www.mersenne.org/bench.htm >Another option for slow machines is ECM factoring. See >http://www.mersenne.org/ecm.htm for details (this is not an >automated project) >If someone wants to volunteer to improve factoring performance that >would be great. The P4 could use an SSE2 implementation. CPU-specific >factoring code over 64 bits could be written. > >While factoring could probably be improved tens of percent, it has not >been a high priority item for me. A 10% boost in factoring speed lets >you factor (on average) 10% deeper, which finds about 1 more factor in >every 650 exponents. That isn't a great throughput improvement for >the GIMPS project. >-- George My factoring machine speed is k6 400Mhz , and I know of the benchmark pages, but there are no factoring benchmarks, only LL. >George Woltman suggested ECM factoring to you as a possibility. snip snip >Good luck! And I would be happy to answer any questions you might have. > >Phil Moore >Lane Community College >Eugene, Oregon I will look into the ECM and P-1 factoring, it somehow frustrates me that LL test tell you that it is no prime, without knowing a factor. >Whilst I was able to get reasonably close to the performance of >George's code for trying the factor - possibly even a tiny bit better >for factors with only just over 2^64 - I got nowhere near the >performance of his candidate elimination code. Hm, do I see here a chalenge for the dark winter nights ? snip snip >The other way to look at this (same conclusion) is that factoring is >way, way ahead of LL testing, so any perceived inefficiency is not >critical. >Regards >Brian Beesley So, forget trial factoring for the next months, and do only LL ? George de Fockert _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
