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Date: Tue, 5 Feb 2002 16:45:11 -0200 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: Pavel Machek <pavel@suse.cz>
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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On Tue, 5 Feb 2002, Pavel Machek wrote:

> > > > 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...

Why not ?

If the pages are present (read-ahead) and the page table
is present, I see no reason why we couldn't fill in 32
page table entries at once.

Rik
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