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From: John Baldwin <jhb@freebsd.org>
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	(bigwig.baldwin.cx); Wed, 09 Nov 2011 09:56:27 -0500 (EST)
Cc: Bruce Cran <bruce@cran.org.uk>, Tim Kientzle <tim@kientzle.com>,
	Jilles Tjoelker <jilles@stack.nl>, Ed Schouten <ed@80386.nl>,
	Alfred Perlstein <alfred@freebsd.org>, arch@freebsd.org
Subject: Re: [PATCH] fadvise(2) system call
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On Wednesday, November 09, 2011 1:18:07 am Tim Kientzle wrote:
> It's not at all obvious.
> 
> If I have 1GB of cache and I'm going
> to generate and then read back a 2GB file,
> the best strategy is to hold the first
> 1GB in cache.
> 
> If I'm going to write the file and it will never be
> read back, then the best strategy is to not
> cache any of it.
> 
> Sometimes, a program knows which of
> these is likely, but if it doesn't know, it shouldn't
> say.

Exactly.

-- 
John Baldwin