Open Stack

On 12/03/2013 04:08 AM, Daniel P. Berrange wrote:
> On Tue, Dec 03, 2013 at 01:47:31AM -0800, Gary Kotton wrote:
>> Hi,
>> I think that this information should be used as part of the scheduling
>> decision, that is hosts that are to be selected should be excluded if they
>> do not have the necessary resources available. It will be interesting to
>> know how this is going to fit into the new scheduler that is being
>> discussed.
>
> The CPU topology support shouldn't have any interactions with, nor
> cause any failures post-scheduling. ie If the host has declared that
> it has sufficient resources to run a VM with the given vCPU count,
> then that is sufficient.

What if we want to do more than just specify a number of vCPUs?  What if 
we want to specify that they need to all come from a single NUMA node? 
Or all from different NUMA nodes?  Or that we want (or don't want) them 
to come from hyperthread siblings, or from different physical sockets.

This sort of things is less common in the typical cloud space, but for 
private clouds where the overcommit ratio might be far smaller and 
performance is more of an issue they might be more desirable.

Chris