For my tests I used version GROMACS 3.3 The Gromacs page does not mention what version was used for the benchmarks reported in their table.
-- Doug > On Sat, 2006-06-17 at 11:34, Mark Hahn wrote: >> > >> desktop (32 bit PCI) cards. I managed to get 14.6 HPL GFLOPS >> > >> and 4.35 GROMACS GFLOPS out of 8 nodes consisting of hardware >> > > ... >> > >> As a point of reference, a quad opteron 270 (2GHz) reported >> > >> 4.31 GROMACS GFLOPS. >> > > >> > > that's perplexing to me, since the first cluster has semp/2500's, >> > > right? that's a 1.75 GHz K8 core with 128K L2 and 64b memory >> > > interface. versus the same number of 2.0 GHz, 1M cores each with >> > > 4x 128b memory. I really wouldn't expect them to be that close - >> > > any speculation on why GROMACS runs so poorly on the much better >> > > SMP machine? >> > >> > <googling for motherboard specs> >> > Aha, Socket 462. The Semprons he used are K7 based. >> >> OK, even more so - how does an even older cpu with lower clock, >> slower memory and only gigabit interconnect beat a quad-opt. >> it seems like some other factors were determining performance. > > Could anyone comment on what version of GROMACS was being used? This > code tends to use computational kernels coded in assembly, and until 3.3 > released, there were no x86_64 assembly kernels. The configure script > wasn't smart enough to figure out that an Opteron could run the x86 > assembly, so it would use auto-generated fortran or C code instead. > > Hacking the configure script to use x86 assembly and compiling 32-bit > resulted in about a 2x speedup on Opteron. I believe the new x86_64 > kernel and 64-bit compilation in GROMACS 3.3 is even faster, but I don't > have numbers on hand. > > -Kevin > > >> >> _______________________________________________ >> Beowulf mailing list, [email protected] >> To change your subscription (digest mode or unsubscribe) visit >> http://www.beowulf.org/mailman/listinfo/beowulf > > _______________________________________________ > Beowulf mailing list, [email protected] > To change your subscription (digest mode or unsubscribe) visit > http://www.beowulf.org/mailman/listinfo/beowulf > -- Doug _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
