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Date: Wed, 08 Dec 2004 21:45:00 +0100
From: Jesper Juhl <juhl-lkml@dif.dk>
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To: Bill Davidsen <davidsen@tmr.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Limiting program swap
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Bill Davidsen wrote:
> I have several machine of various memory sizes which suffer from really 
> poor performance when doing backups. This appears to be because all the 
> programs other than the backup quickly get swapped to make room for i/o 
> buffers.
> 
> Is there some standard portable way to prevent this, either by reserving 
> some memory for programs which will not get swapped regardless of i/o 
> pressure, or alternatively limiting the total memory used for i/o 
> buffers, dcache, and similar things?
> 

I'm wondering if turning the /proc/sys/vm/swappiness knob would help, 
but I'll honestly admit that I don't know.

-- 
Jesper Juhl