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To: Scott Long <scottl@samsco.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sun, 08 May 2005 07:05:11 MDT."
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Date: Sun, 08 May 2005 19:15:25 +0200
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cc: Eric Anderson <anderson@centtech.com>
Subject: Re: Very low disk performance on 5.x 
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In message <427E0E87.1040701@samsco.org>, Scott Long writes:

>The solution is to re-engineer the way that I/O buffers pass through
>the kernel and only assign KVA when needed (for doing software parity
>calculations, for example).

I've hacked up a prototype to do this and there is no doubt that this
is the way we are headed, hopefully sometime in the 7-CURRENT period.

-- 
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.