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Date: Tue, 24 Jul 2001 19:05:36 -0300 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: Marcelo Tosatti <marcelo@conectiva.com.br>
Cc: Daniel Phillips <phillips@bonn-fries.net>, <linux-kernel@vger.kernel.org>,
        Ben LaHaise <bcrl@redhat.com>, Mike Galbraith <mikeg@wen-online.de>
Subject: Re: [RFC] Optimization for use-once pages
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On Tue, 24 Jul 2001, Marcelo Tosatti wrote:
> On Tue, 24 Jul 2001, Daniel Phillips wrote:
>
> > Today's patch tackles the use-once problem, that is, the problem of
>
> Well, as I see the patch should remove the problem where
> drop_behind() deactivates pages of a readahead window even if
> some of those pages are not "used-once" pages, right ?
>
> I just want to make sure the performance improvements you're
> seeing caused by the fix of this _particular_ problem.

Fully agreed.

Especially since it was a one-liner change from worse
performance to better performance (IIRC) it would be
nice to see exactly WHY the system behaves the way it
does.  ;)

Reading a bunch of 2Q, LRU/k, ... papers and thinking
about the problem very carefully should help us a bit
in this.  Lots of researches have already looked into
this particular problem in quite a lot of detail.

regards,

Rik
--
Executive summary of a recent Microsoft press release:
   "we are concerned about the GNU General Public License (GPL)"


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