On 07/17/2012 05:59 PM, zxq9 wrote:
> On 07/18/2012 07:46 AM, Orion Poplawski wrote:
>> On 07/17/2012 04:17 PM, zxq9 wrote:
>>> On 07/18/2012 06:55 AM, Orion Poplawski wrote:
>>>> While staring at top on my kvm server waiting for it to crash, I noticed
>>>> that my idle Fedora kvm guests appear to be consuming between 8-12% cpu
>>>> while my idle SL6 guests appear to be consuming between 0.3-2% cpu as
>>>> shown in the qemu-kvm processes in top.
>>>>
>>>> Does anyone have any insight as to why this would be the case?
>>>
>>> That depends heavily on what version of Fedora they are (particularly
>>> Rawhide
>>> instances), and what services they are running.
>>
>> Well, I have a Fedora 17 instance running now with nothing but kernel
>> processes and the qemu-kvm process still shows using 7-8% cpu.
>
> There's pretty much no such thing as a F17 instance with nothing but the
> kernel running. Can you log in to one of the instances and check what top says
> is running (like the top 10 or so processes by CPU use)?
>

Not at that point, because I'd killed everything but the kernel and systemd :)

> The odds that kvm itself is spinning more just to keep F17 alive over anything
> else is remote, but the odds that something in F17 defaults to wasteful
> behavior is quite high (particularly if you are hosting X with Gnome Shell --
> there are any number of things that waste cycles in there).
>
> That said, you may be affected by the Fedora version of the July 1st leap
> second bug where processes like qpidd eat 1 core (or equivalent) entirely
> while stuck in an infinite loop (this behavior can survive a reboot). If you
> see a single process in top eating a significant percentage of its allocated
> resources try:
>
> date; date $(date +"%m%d%H%M%C%y.%S"); date
>
> on the misbehaving Fedora instance and see if things change.

There are no busy processes.  Load avg is at or less than 0.05.

-- 
Orion Poplawski
Technical Manager                     303-415-9701 x222
NWRA, Boulder Office                  FAX: 303-415-9702
3380 Mitchell Lane                       [log in to unmask]
Boulder, CO 80301                   http://www.nwra.com