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On 02/06/2017 06:19 PM, Manuel Sopena Ballesteros wrote:
> Hi,
>
> I am trying to isolate my instances by cpu socket in order to improve my NUMA
> hardware performance.

<snip>

> What would be the recommended way to do this?

In order to dedicate a host CPU to each virtual CPU, set the flavor extra spec 
"hw:cpu_policy" to "dedicated", or if the flavor extra spec is not set you can 
set the image property "hw_cpu_policy" to dedicated.

This will also ensure that each guest NUMA node is mapped to a single host NUMA 
node.  By default the CPU/RAM is divided evenly across all guest NUMA nodes.  If 
that's not possible (5 vCPUs and 2 guest nodes, for example) then you have to 
explicitly specify how to distribute the resources across the guest NUMA nodes.

You may also find some benefit from specifying that the guest should be backed 
by RAM hugepages instead of 4K pages.

Chris