Hi, At 12:46 AM 11/27/2001 +0100, george de fockert wrote: >One of my machines does trial factoring. >Now in the M17900000 range, factoring to 2^66. >This takes a very long time, is it better to let it double check ?
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) >Or is it time for a more efficient trial factor implementation (if possible >?). 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 _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
