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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] balloon driver
Date: Wed, 5 Jul 2006 15:52:11 +0100
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To: qemu-devel@nongnu.org

On Wednesday 05 July 2006 03:58, Eric L wrote:
> I've been playing around with QEMU the past few days and have been
> quite impressed.  One thing I wondered about: it seems that most of
> the other virtualization schemes have some sort of balloon driver to
> reclaim unused (cached) guest memory.  (VMWare, Xen and I think user
> mode linux has something too).  It seems like a pretty good idea to
> me, but from my searching, it would appear that QEMU does not have
> anything similar.  Is this correct?  If so, is there a reason why?

Partly because qemu is just a normal user application. It can be swapped out 
by the host OS just like any other process. Adding a few Gb of extra swap and 
letting the host OS figure it out should get you 90% of the benefit.

Paul