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Date: Mon, 10 Feb 2003 13:25:38 +0100
From: Andrea Arcangeli <andrea@suse.de>
To: Andrew Morton <akpm@digeo.com>
Cc: Nick Piggin <piggin@cyberone.com.au>, reiser@namesys.com,
       jakob@unthought.net, david.lang@digitalinsight.com,
       riel@conectiva.com.br, ckolivas@yahoo.com.au,
       linux-kernel@vger.kernel.org, axboe@suse.de
Subject: Re: stochastic fair queueing in the elevator [Re: [BENCHMARK] 2.4.20-ck3 / aa / rmap with contest]
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On Mon, Feb 10, 2003 at 04:12:45AM -0800, Andrew Morton wrote:
> traffic, etc would be expected.   Could be that sending out a
> request which is larger than a track is saving a rev of the disk
> for some reason.

I'm guessing something on those lines yes, I doubt it's purerely in core
overhead that makes that much difference. Just for completeness, I never
read this in literature or data sheets, this is all out of pratical
experience, so we can't exclude something odd in the scsi layer, but I
very much doubt, the only thing that might explain it is to waste cpu
and we know it's not wasting it.

Andrea
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