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On Friday, September 26, 2014 03:09:05 PM Daniel P. Berrange wrote:

> > 1. What happens on an overcommit for the number of guest CPUs?
> > 
> >    - For example, if I have a system with 2 sockets 4 cores each,
> >    what
> > 
> > would happen if I have 2 guests, each one wanting 6 cores (assuming
> > this is not in violation of the hw:cpu_max_cores)?
> > 2. What happens on an overcommit on memory?
> 
> The memory and CPU overcommit settings are still honoured when Nova
> does NUMA placement. eg if you have a host with 2 NUMA nodes, each
> with 4 physical CPUs and CPU overcommit ratio of x3, then Nova will
> treat this as being a system with 2 NUMA nodes, each with 12 CPUs.
> Similarly for memory overcommit.
> 

So in the scenario you describe above, each guest configuration would be 
constrained to one NUMA node (since the NUMA node would present itself 
logically as having 12 CPUs)?  

I was trying to think of a scenario where the guest configuration would 
have to split up among more than one NUMA node. 

Regards,
Sean Toner