Thanks Guillermo, I didn't spot those options. But I'm still confused as to what they really mean. Can you split an L-L test into parallel threads over say 8 cpu's, and get the answer ~ 8 times faster ? I had thought that the L-L algorithm was strictly sequential. I guess you can exploit OpenMP and get a 2x or 3x/4x speedup in the short pieces of code where stuff is really happening in classical "parallel", but my guess would have been that would end up getting you about a 1.2X - 1.5X speedup overall. I apologize I'm making these wild generalisations with no knowledge of the L-L code.
To answer Max: yes I'm sure for throughput I should just run 8 copies of single-thread L-L, and I hope to be able to try that. But I have a funny situation here: almost exclusive access to some 4p/8p/16p Itanium2 machines for periods of up to say two weeks, plus access to anything from 32p to 256p slices of bigger machines for say a few days. So an MP version of Glucas L-L that truly scales would let me finish full L-L runs inside these time limits on all the machines. Cheers, Greg E -----Original Message----- From: Guillermo Ballester Valor [mailto:[EMAIL PROTECTED] Sent: Saturday, 2 April 2005 7:51 PM To: [email protected] Cc: Greg Edwards Subject: Re: [Prime] Multi-processor LL tests Er.. Of course, the link is not correct, I forgot to change 'localhost' by 'www.oxixares.com': http://www.oxixares.com/glucas/doc/Configure-Make-and-Install.html#Configure %20Make%20and%20Install El S�bado, 2 de Abril de 2005 10:24, Guillermo Ballester Valor escribi�: > On page: > > http://localhost/glucas/doc/Configure-Make-and-Install.html#Configure%20Mak >e%20and%20Install > > you will see the multithread options you can use at './configure' time. You > can use Sunmp (for Sun compilers), Openmp (for compilers supporting that) > and POSIX threads. > -- Guillermo Ballester Valor [EMAIL PROTECTED] Ogijares, Granada SPAIN Linux user #117181. See http://counter.li.org/ Public GPG KEY http://www.oxixares.com/~gbv/pubgpg.html _______________________________________________ Prime mailing list [email protected] http://hogranch.com/mailman/listinfo/prime
