linux-kernel - LowFree/LowMem problem

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Date:	Mon, 21 Jan 2008 06:32:41 +0100
From:	Matthias Wolle <Matthias.Wolle@....de>
To:	linux-kernel@...r.kernel.org
Subject: LowFree/LowMem problem

Hi,

my company is running several servers with kernel 2.6.23.12.  This are Dual 
Quad Core servers (CPU Intel) with 16GB RAM using a 32Bit kernel.
After some days nicely running the oom killer killed our processes.
Our research discovered that the free low memory was reduced to about 11MB. We 
found out that the decreasing of low memory is related to the count off 
executed and ended programs.

I could reproduce the same bug on a maschine with 2GB RAM without PAE (option 
4GB HIGHMEM). The following code reproduces the bug.

#!/bin/sh

while [ true ]; do
	cat /proc/meminfo| grep LowFree
done

Please run this script only on a test system. It reduces the low memory quite 
fast (within minutes). 

The latest available kernel 2.6.24-rc8 is also affected.

Please fell free to request more information from me.
Please always CC to me, I'm not subscribed.

Thanks for reading

Matthias
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