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To: Robert Watson <rwatson@freebsd.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 31 Jul 2003 19:08:17 EDT."
             <Pine.NEB.3.96L.1030731190517.85739A-100000@fledge.watson.org> 
Date: Fri, 01 Aug 2003 09:06:18 +0200
Message-ID: <5893.1059721578@critter.freebsd.dk>
cc: arch@freebsd.org
Subject: Re: headsup: swap_pager.c 
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In message <Pine.NEB.3.96L.1030731190517.85739A-100000@fledge.watson.org>, Robe
rt Watson writes:
>
>On Thu, 31 Jul 2003, Poul-Henning Kamp wrote:
>
>> I am in the process of changing the on-disk layout policy used by the
>> swap_pager. 
>
>Do you anticipate any performance changes as a result of this change? 

Anticipate ?  No.
Be surprised by improvements ? No.

The striping code limits the I/O size for paging activity to a small
size.  By laying out each disk sequentially in the "swap device" we
can increase that size to what our I/O system can lift.

-- 
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.