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Date: Fri, 31 Oct 2003 01:28:46 -0800
From: Andrew Morton <akpm@osdl.org>
To: age <ahuisman@cistron.nl>
Cc: linux-kernel@vger.kernel.org, nuno.silva@vgertech.com
Subject: Re: READAHEAD
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age <ahuisman@cistron.nl> wrote:
>
> > Lots of people have been reporting this.  It's rather weird.
>   >
>   > Is the same effect observable when reading a large file, or is it only
>   > observable via `hdparm -t'?
>   >
> 
>  Hi Andrew,
> 
>  Here are some tests with bonnie++.

Like so many of these things, bonnie++ is generally far, far too complex
for kernel performance tuning.

Please, just use time, cat, dd, etc.

	mount /dev/xxx /mnt/yyy
	dd if=/dev/zero of=/mnt/yyy/x bs=1M count=1024
	umount /dev/xxx
	mount /dev/xxx /mnt/yyy
	time cat /mnt/yyy/x > /dev/null

nice'n'easy.