F15 / VirtualBox

[Richard W.M. Jones]

On Fri, Jun 10, 2011 at 02:30:46PM +0200, Thomas Sailer wrote:
> On Fri, 2011-06-10 at 10:24 +0200, Tomasz Torcz wrote:
> 
> >  - it's memory deduplication reimplements what already in-kernel (for the
> >    sake of cross platform)
> 
> Kernel deduplication runs amok on my machine. When I have two guests,
> one Windows, one Rawhide, running under kvm/qemu, kernel deduplication
> uses up one CPU core. For no benefit, I suspect there isn't much to
> deduplicate between Windows and Rawhide.

There's a bug for these issues (no resolution though):

https://bugzilla.redhat.com/show_bug.cgi?id=541230

Originally I had ksmd turned off, but since ~ Fedora 14 I've not had
any trouble with it at all.

It's also worth noting that there are lots of knobs to tune KSM in
/etc/ksmtuned.conf.  More information is here:

http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization/chap-KSM.html

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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