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Date: Mon, 07 Oct 2002 13:14:23 -0700
From: Andrew Morton <akpm@digeo.com>
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To: Daniel Phillips <phillips@arcor.de>
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Subject: Re: The reason to call it 3.0 is the desktop (was Re: [OT] 2.6 not 3.0 
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Daniel Phillips wrote:
> 
> This is easy to verify: say you have 100 MB of kernel source stored in, say,
> 50 different clumps on disk.

Disks use segmentation on their readahead buffers.  Typically four-way.
So they will only buffer four different chunks of disk at a time.

If you're reading from 50 different places on disk, the disk keeps
invalidating readahead at the segment level.
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