From: Al Boldi <a1426z@gawab.com>
To: linux-kernel@vger.kernel.org
Subject: Re: [RFC] Limit the size of the pagecache
Date: Thu, 25 Jan 2007 09:42:47 +0300
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Rik van Riel wrote:
> Christoph Lameter wrote:
> > This is a patch using some of Aubrey's work plugging it in what is IMHO
> > the right way. Feel free to improve on it. I have gotten repeatedly
> > requests to be able to limit the pagecache.
>
> IMHO it's a bad hack.
>
> It would be better to identify the problem this "feature" is
> trying to fix, and then fix the root cause.

Ok, here is the problem:  kswapd.

Limiting the page-cache memory inhibits invoking kswapd needlessly, aiding 
performance and easing OOM pressures.

I tried the patch; it works.

But it needs a bit of debugging.  Setting pagecache_ratio = 1 either 
deadlocks or reduces thru-put to < 1mb/s.


Thanks!

--
Al

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