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Date: Tue, 20 Nov 2001 16:21:32 -0800 (PST)
Message-Id: <20011120.162132.25418218.davem@redhat.com>
To: riel@conectiva.com.br
Cc: akpm@zip.com.au, dmaas@dcine.com, linux-kernel@vger.kernel.org
Subject: Re: Swap
From: "David S. Miller" <davem@redhat.com>
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   From: Rik van Riel <riel@conectiva.com.br>
   Date: Tue, 20 Nov 2001 22:19:26 -0200 (BRST)

   On Tue, 20 Nov 2001, David S. Miller wrote:
   > The Apache folks were keeping it mapped across requests,
   > so even if it was "primed" (ie. pre-faulted), a read() into
   > a static buffer was still significantly faster.
   
   Interesting.  I wonder how read() and mmap() compare when the
   data is in highmem pages and we're facing a kmap()/kunmap()
   for read() ...

Probably, the performance drops for read() to be equivalent,
or slightly below, mmap() peformance.  That would be my guess.

Franks a lot,
David S. Miller
davem@redhat.com
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