Messages in this thread | | | Date | Fri, 21 Jun 2002 07:59:15 -0500 (CDT) | From | Jesse Pollard <> | Subject | Re: latest linus-2.5 BK broken |
| |
Martin Dalecki <dalecki@evision-ventures.com>: >Yes HT gives 12%. naive SMP gives 50% and good SMP (aka corssbar bus) >gives 70% for two CPU. All those numbers are well below the level >where more then 2-4 makes hardly any sense... Amdahl bites you still if you >read it like: ...
I think your numbers are a little low - I've seen between 50%-80% on master/slave SMP depending on the job. 50% if both processess are heavily syscall oriented, 75% (or therabouts) when both processes are more normally balanced, and 80% if both processes are more compute bound.
Good SMP, with a crossbar switch buss should give close to 95%. Good SMP alone should give about 75%.
My expierence with good crossbar switch is based on Cray UNICOS/YMP/SV hardware. A well tuned hardware platform, and slightly less well tuned SMP implementation, though the UNICOS 10 rewrite may have fixed the SMP implementation.
------------------------------------------------------------------------- Jesse I Pollard, II Email: pollard@navo.hpc.mil
Any opinions expressed are solely my own. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |