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To: Luigi Rizzo <rizzo@icir.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sun, 21 Jan 2007 14:00:19 PST."
	<20070121140019.A83688@xorpc.icir.org> 
Date: Sun, 21 Jan 2007 22:10:23 +0000
Message-ID: <18141.1169417423@critter.freebsd.dk>
Sender: phk@critter.freebsd.dk
Cc: Ivan Voras <ivoras@fer.hr>, freebsd-arch@freebsd.org
Subject: Re: bzero & bcopy alignment 
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In message <20070121140019.A83688@xorpc.icir.org>, Luigi Rizzo writes:
>On Sun, Jan 21, 2007 at 10:41:09PM +0100, Ivan Voras wrote:
>> Following recent discussion on alignment of bzero() and bcopy(), I've
>> added some statistics collecting code to bzero() and bcopy() for
>> practice (on a RELENG_6 box), and here are the cumulative results for
>> argument alignment:
>
>i think these profiles depend heavily on the hardware
>and usage patterns.

Undoubtedly, but on the other hand, a lot of them operate on
structs and other data laid out by the compiler, so the
unaligned calls are special cases.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.