From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Hommey <mh-YmoObPS1fuhg9hUCZPvPmw@public.gmane.org>
Subject: Containers and /proc/sys/vm/drop_caches
Date: Wed, 5 Jan 2011 10:40:22 +0100
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[Copy/pasted from a previous message to lkml, where it was suggested to
 try containers@]

Hi,

I noticed that from within a lxc container, writing "3" to
/proc/sys/vm/drop_caches would flush the host page cache. That sounds a
little dangerous for VPS offerings that would be based on lxc, as in one
VPS instance root user could impact the overall performance of the host.
I don't know about other containers but I've been told openvz isn't
subject to this problem.
I only tested the current Debian Squeeze kernel, which is based on
2.6.32.27.

Cheers,

Mike