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From: Oliver Neukum <oliver@neukum.name>
To: Rik van Riel <riel@conectiva.com.br>,
       Xuan Baldauf <xuan--lkml@baldauf.org>
Subject: Re: Heuristic readahead for filesystems
Date: Wed, 11 Sep 2002 19:20:58 +0200
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Am Mittwoch, 11. September 2002 18:42 schrieb Rik van Riel:

> Your observation is right, but I'm not sure how much it will
> matter if we start reading the file at stat() time or at
> read() time.
>
> This is because one disk seek takes about 10 million CPU
> cycles on modern systems and we'll have completed the stat(),
> open() and started the read() before the disk arm has started
> moving ;)

Do we gain by sorting the disk accesses ?
How about savings due to better cooperation with the IO
scheduler?

	Regards
		Oliver

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