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Date: Tue, 20 Nov 2001 14:23:38 -0800
From: Andrew Morton <akpm@zip.com.au>
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To: "David S. Miller" <davem@redhat.com>
CC: riel@conectiva.com.br, dmaas@dcine.com, linux-kernel@vger.kernel.org
Subject: Re: Swap
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"David S. Miller" wrote:
> 
>    From: Rik van Riel <riel@conectiva.com.br>
>    Date: Tue, 20 Nov 2001 20:05:05 -0200 (BRST)
> 
>    Consider this a VM bug, mmap() really should be more efficient.
> 
> read() is always going to be faster until mmap() can
> use large page mappings for the user.  This is why
> mmap() is slower.
> 
> Even if the whole thing is cached in memory, read() will
> always be faster.

Could you please explain further?  What's more expensive
than the copy?
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