[libvirt] [PATCH 12/12] nodedev: Export NUMA node locality for PCI devices

[Daniel P. Berrange]

On Thu, May 29, 2014 at 10:32:46AM +0200, Michal Privoznik wrote:
> A PCI device can be associated with a specific NUMA node. Later, when
> a guest is pinned to one NUMA node the PCI device can be assigned on
> different NUMA node. This makes DMA transfers travel across nodes and
> thus results in suboptimal performance. We should expose the NUMA node
> locality for PCI devices so management applications can make better
> decisions.
> 
> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
> ---
> 
> Notes:
>     All the machines I have tried this on had only -1 in the
>     numa_node file. From the kernel sources it seems that this is the
>     default, so I'm not printing the <numa/> element into the XML in
>     this case. But I'd like to hear your opinion.

Yes, I believe '-1' means that there is no NUMA locality info
available for the device, so it makes sense to skip this.

Regards,
Daniel
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