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Date: Tue, 20 Nov 2001 22:19:26 -0200 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: "David S. Miller" <davem@redhat.com>
Cc: <akpm@zip.com.au>, <dmaas@dcine.com>, <linux-kernel@vger.kernel.org>
Subject: Re: Swap
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On Tue, 20 Nov 2001, David S. Miller wrote:
>    From: Rik van Riel <riel@conectiva.com.br>
>    Date: Tue, 20 Nov 2001 21:35:40 -0200 (BRST)
>
>    On Tue, 20 Nov 2001, David S. Miller wrote:
>    > TLB misses add to the cost, and this overhead is more than
>    > "noise".

> 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() ...

regards,

Rik
-- 
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