On 07/03/2014 08:29 AM, Gleb Voronich wrote:
> Eric Blake <mailto:eblake@redhat.com>
> >
> > In the case of the memory balloon device, libvirt CAN provide stats from
> > the guest, because of the way the balloon device works. But if you
> > aren't using a balloon, or if the guest is not cooperative, this won't
> > work. Better would be a guest-agent command for getting at this
> > information (but again, you are relying on guest cooperation). In
> > short, libvirt is great at stats from the HOST point of view, but for
> > stats from the GUEST point of view, you are often better off using the
> > same mechanisms that you would for getting stats from a remote bare
> > metal machine, without needing libvirt in the mix.
>
> Thanks Eric.
>
> 1. I use the balloon for all of my guests:
> <memballoon model='virtio'>
> But how can I get stats?
virDomainMemoryStats() gets those stats, if qemu is new enough to
provide them, and if the guest cooperates to provide them.
>
> 2. I've tried the latest QEMU GA 2.0.0
Right now, there are no memory stats available through the guest agent,
only through the balloon device.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library
http://libvirt.org