From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Hommey <mh@glandium.org>
Subject: Re: [PATCH v4] Threaded grep
Date: Tue, 26 Jan 2010 18:19:00 +0100
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Cc: Benjamin Kramer <benny.kra@googlemail.com>,
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To: Linus Torvalds <torvalds@linux-foundation.org>
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On Tue, Jan 26, 2010 at 08:56:50AM -0800, Linus Torvalds wrote:
<snip>
> although it is worth noting that that machine has an Intel SSD, which is 
> why it gets sped up so much by parallel IO (there's no seek penalty, and 
> it is able to read multiple channels in parallel, so this gives much 
> better IO patterns for it - with rotational media the numbers might be 
> very different).

For rotational disks, using FIEMAP to get the position of the files on
disk to reorder how we read them could help.

Mike