From owner-freebsd-performance@FreeBSD.ORG  Sat Dec 23 17:07:33 2006
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Date: Sat, 23 Dec 2006 17:40:25 +0100
From: "Attilio Rao" <attilio@freebsd.org>
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To: "David Xu" <davidxu@freebsd.org>
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References: <458B3651.8090601@paradise.net.nz>
	<20061222222757.G18486@delplex.bde.org>
	<20061222202933.709d2279@Magellan.Leidinger.net>
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Cc: Mark Kirkwood <markir@paradise.net.nz>,
	Alexander Leidinger <Alexander@leidinger.net>,
	Adrian Chadd <adrian@freebsd.org>,
	freebsd-performance@freebsd.org, Bruce Evans <bde@zeta.org.au>
Subject: Re: Cached file read performance
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2006/12/23, David Xu <davidxu@freebsd.org>:
> On Saturday 23 December 2006 03:29, Alexander Leidinger wrote:
>
> > I want to point out http://www.freebsd.org/projects/ideas/#p-memcpy
> > here. Just in case someone wants to play around a little bit.
> >
> > Bye,
> > Alexander.
>
> I have read the code, if a buffer is not aligned at 16 bytes boundary,
> it will not use FPU to copy data, but user buffer is not always 16 bytes
> aligned.

If the buffer is not aligned, speedup improvement is so small to be near at 0%.

Attilio


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