[libvirt-users] Setting CPU type for a vm

[Daniel P. Berrange]

On Thu, Jul 19, 2012 at 07:54:49AM -0600, Eric Blake wrote:
> On 07/18/2012 08:45 PM, Mauricio Tavares wrote:
> >     I have a Windows XP vm and would like to know how should I set its
> > cpu so it is seen by the vm as a proper 32bit one. In its xml file, I have
> > 
> >   <os>
> >     <type arch='i686' machine='rhel6.2.0'>hvm</type>
> 
> That's the correct way.
> 
> > and this is what virsh thinks my vm has:
> > 
> > [root at vmhost ~]# virsh vcpuinfo xp
> > VCPU:           0
> 
> This looks like a bug - a guest cannot exist without at least one vcpu.
> 
> > CPU:            2
> 
> That only says your host has 2 cpus that the guest can utilize; it says
> nothing about what type of cpu the guest will see.

You're mis-interpreting the data here.  'vpucinfo' info repeats these
four lines of data per VCPU.

So this is saying that the first vCPU, #0, is running running on host
CPU #2.

The total number of guest CPUs is shown by 'virsh dominfo'

The total number of host CPUs is shown by 'virsh nodeinfo'

Daniel
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