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RE: spec2k comparison of gcc 4.1 and 4.2 on AMD K8
Honza,
> Well, rather than unstable, they seems to be more memory layout
> sensitive I would say. (the differences are more or less reproducible,
> not completely random, but independent on the binary itself. I can't
> think of much else than memory layout to cause it). I always wondered
> if things like page coloring have chance to reduce this noise, but I
> never actually got around trying it.
You didn't mention the processors in your systems, but I wonder if they are dual-core. If so, perhaps it's got to do with the fact that each K8 core has its own L2, whereas C2 chips have a shared L2. Then, try preceding "runspec" with "taskset 0x02" to avoid the process from hopping between cores and finding cold caches (though the kernel strives to stick a process to a single core, it's not perfect).
HTH
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Evandro Menezes AMD Austin, TX