Re: 'cp file1 file2' takes 2x`sizeof(file)` cache (2.3.99-pre9-2)

From: Jeff Garzik (jgarzik@mandrakesoft.com)
Date: Wed May 17 2000 - 16:11:53 EDT

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    Andreas Bombe wrote:
    >
    > On Tue, May 16, 2000 at 11:57:25PM +0200, iafilius@xs4all.nl wrote:
    > > Just noticed while copying a (large/tested with 60MB) file it takes about
    > > twice the file's size in cache (which takes it from free memory).
    > >
    > > This must be because kernel doesn't know about the same files,
    > > and caches them separate.
    >
    > They are separate files after all, so what should it do? Do a memcmp
    > over all of its caches to find whether there are identical cache
    > pages?

    It seems like "cp file1 file2" is very analagous to sendfile(2)
    actually... :)

            Jeff 

    -- 
Jeff Garzik              | Liberty is always dangerous, but
Building 1024            | it is the safest thing we have.
MandrakeSoft, Inc.       |      -- Harry Emerson Fosdick

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