Il giorno mar, 15/12/2009 alle 12.46 -0600, Justin M. Forbes ha scritto:
On Tue, 2009-12-15 at 19:31 +0100, Dario Lesca wrote:
> Il giorno mar, 15/12/2009 alle 11.28 -0600, Justin M. Forbes ha scritto:
> >
> > > Is this normal?
> > KSM has a penalty in that it requires CPU cycles to scan for usable
> > pages.
>
> > This should be mitigated by the ksm service turning the scanner off
> > when it is not needed.
> > Do you have any more information on the hardware profile? Is there a
> > smolt profile for this system?
>
> Yes :
>
http://www.smolts.org/client/show_all/pub_9da3c016-41da-42f1-b2c3-05f31ff...
>
> > > It's possible do something to improve the situation?
> > Is the ksmtuned service running?
> Yes:
> [root@lesca ~]# /etc/init.d/ksmtuned status
> ksmtuned (pid 1522) in esecuzione...
>
>
> > If not, please turn it on. Optionally you can also turn off ksm and
> > ksmtuned.
>
> I have turn off ksm and ksmtuned but the qemu use always 15% cpu... none
> is changed.
This is most likely an manifestation of
https://bugzilla.redhat.com/show_bug.cgi?id=478317 and hopefully we will
have a fix soon.