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Date: Fri, 22 Dec 2006 13:09:48 +0900
From: "Adrian Chadd" <adrian@freebsd.org>
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To: "David Xu" <davidxu@freebsd.org>
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Cc: freebsd-performance@freebsd.org, Mark Kirkwood <markir@paradise.net.nz>
Subject: Re: Cached file read performance
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On 22/12/06, David Xu <davidxu@freebsd.org> wrote:

> I suspect in such a test, memory copying speed will be a key factor,
> I don't have number to back up my idea, but I think Linux has lots
> of tweaks, such as using MMX instruction to copy data.

I had the oppertunity to study the AMD Athlon XP Optimisation guide
and noted their example copy routine, optimised for the chipset, was
quite a hell of a lot faster over a straight block copy.

Has anyone here done any similar modifications to optimise
copyin/copyout? I can't imagine it'd be a bad thing to have.


Adrian