On Thu, 8 Dec 2005, Min Xu (Hsu) wrote:
> Perhaps because P4 is already doing H/W prefetching?
>
> http://www.tomshardware.com/2000/11/20/intel/page5.html
>
> I ran the test program on an opteron 2.2G:
> Got slowdown.
>
> I ran it on a PIII 650M:
> looks like some speedup to me.
>
Ok, I see ... so this optimization relies on the CPU type and even speed.
If many programs are fighting for L2 cache, then things will be screwed
up.
Regards,
Qingqing
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