Message-ID: <4067114D.7050606@pobox.com>
Date: Sun, 28 Mar 2004 12:54:21 -0500
From: Jeff Garzik <jgarzik@pobox.com>
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To: Jamie Lokier <jamie@shareable.org>
CC: Nick Piggin <nickpiggin@yahoo.com.au>, linux-ide@vger.kernel.org,
       Linux Kernel <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH] speed up SATA
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Jamie Lokier wrote:
> This is what I mean: turn off write cacheing, and performance on PATA
> drops because of the serialisation and lost inter-command time.
> 
> With TCQ-on-write, you can turn off write cacheing and in theory
> performance doesn't have to drop, is that right?

hmmm, that's a good point.  I honestly don't know.  Something to be 
tested, I suppose...

My premature guess would be that you would need a queue depth larger 
than 2 or 4 before performance starts to not-suck.

	Jeff


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