Re: Swap

Rik van Riel (riel@conectiva.com.br)
Tue, 20 Nov 2001 22:19:26 -0200 (BRST)

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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