[PATCH] Mantaining turnstile aligned to 128 bytes in i386 CPUs
Ricardo Nabinger Sanchez
rnsanchez at wait4.org
Wed Jan 17 15:41:17 UTC 2007
On Wed, 17 Jan 2007 15:50:41 +1100 (EST)
Bruce Evans <bde at zeta.org.au> wrote:
> AXP: (my 5 year old system with a newer CPU): movq through MMX is 60%
> faster than movsl for cached moves, but movdqa through XMM is only 4%
> faster. movnt with block prefetch is 155% faster than movsl with no
> prefetch, and 73% faster with no prefetch for both.
> A64 in 32-bit mode: in between P4 and AXP (closer to AXP). movsl doesn't
> lose by so much, and prefetchnta actually works so block prefetch is
> not needed and there is a better chance of prefetching helping more
> than benchmarks.
This PDF is somewhat dated, but perhaps some of it still applies today:
http://cdrom.amd.com/devconn/events/AMD_block_prefetch_paper.pdf
--
Ricardo Nabinger Sanchez <rnsanchez@{gmail.com,wait4.org}>
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