________________________________ From: Jan Heichler [mailto:[EMAIL PROTECTED]
AMD Barcelona, Opteron 2356, dual-socket, 2.3 GHz: http://www.spec.org/omp/results/res2008q2/omp2001-20080325-00291.html SPECompMbase2001 = 17598 Intel Harpertown, Intel Xeon E5440, dual-socket, 2.83 GHz: http://www.spec.org/omp/results/res2008q2/omp2001-20080325-00292.html SPECompMbase2001 = 14789 TE> -- I seem to recall that AMD had a TE> rationale of choosing similarly power-consuming CPUs, but I could be TE> wrong there. > But the Harpertown that the benchmark ran on was not one with FSB1600. And this is/could be a real difference here > since it affects the memory performance. You are right, Jan. I checked that the Supermicro motherboard supported the 1600 MHz FSB, but not the CPU. E5462 (2.8 GHz( and E5472 (3.0 GHz) are processors that have the 1600 Mhz FSB and seem to have the same power specs as the E5440 (80W). The additional FSB speed would certainly make a difference in OMP2001 performance, esp. on memory bandwidth-sensitive codes like swim and mgrid. Here are some measurements I just made on OpenMP STREAM: 8-thread STREAM Copy (GB/s) Harpertown - ---------------- Xeon 5410, 2.33 GHz, 1333 MHz FSB: 6.2 Xeon 5472, 3.0 GHz, 1600 MHz FSB: 7.3 Barcelona - Opteron 2352, 2.1 GHz: 15.7 (the 3 other STREAM components were pretty similar to Copy) These were on 2-socket, 8-core systems. Just a quick test, so not necessarily optimal. But Intel and PathScale compilers got the same OpenMP stream performance on the Xeon processors with high optimization, so that seems like a sign that the executables were pretty good. -Tom ------------------- Cheers, Jan _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf