Re: Is guest OS oriented scheduling welcome?

["Daniel P. Berrange" <berrange@redhat.com>]

On Wed, Apr 22, 2009 at 03:22:54PM +0300, Avi Kivity wrote:
> ????????? wrote:
> >Hello folks,
> >In the past, it was said KVM would like to treat the guest OS threads 
> >differently in scheduling. However, till now, the qemu thread is regarded 
> >as a conventional user thread. Therefore, it is hard to control how much 
> >CPU slices one guest OS can utilize. I don't think a computing cloud 
> >provider likes this idea.

Although the standard scheduler tunables are per thread, it is possible
to put each QEMU process into a separate CGroup, and use the cpu_shares
tunable to control scheduling priority of the guest as a whole, instead
of individual threads. Not sure it this is sufficient for what you
want, but it is one possible option for guest scheduling..

Daniel
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