Re: [PATCH] Mantaining turnstile aligned to 128 bytes in i386 CPUs

On Wed, 17 Jan 2007 15:50:41 +1100 (EST)
Bruce Evans <bde@xxxxxxxxxxx> 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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