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Date: Tue, 5 Feb 2002 14:21:55 +0000
From: Pavel Machek <pavel@suse.cz>
To: Rik van Riel <riel@conectiva.com.br>
Cc: Jeff Garzik <garzik@havoc.gtf.org>, arjan@fenrus.demon.nl,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Radix-tree pagecache for 2.5
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Hi!

> > > the biggest reason for this is that we *suck* at readahead for mmap....
> >
> > Is there not also fault overhead and similar issues related to mmap(2)
> > in general, that are not present with read(2)/write(2)?
> 
> If a fault is more expensive than a system call, we're doing
> something wrong in the page fault path ;)

You can read 128K at a time, but you can't fault 128K...
								Pavel

-- 
Philips Velo 1: 1"x4"x8", 300gram, 60, 12MB, 40bogomips, linux, mutt,
details at http://atrey.karlin.mff.cuni.cz/~pavel/velo/index.html.

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