Re: [libvirt] [PATCH 2/5] docs: Define XML schema for numa tuning and add docs

On Thu, May 05, 2011 at 05:38:27PM +0800, Osier Yang wrote: > Currently we only want to use "membind" function of numactl, but > perhaps more other functions in future, so introduce element > "<numatune>", future NUMA tuning related XML stuffs should go > into it. > --- > docs/formatdomain.html.in | 17 +++++++++++++++++ > docs/schemas/domain.rng | 20 ++++++++++++++++++++ > 2 files changed, 37 insertions(+), 0 deletions(-) > > diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in > index 5013c48..6da6465 100644 > --- a/docs/formatdomain.html.in > +++ b/docs/formatdomain.html.in > @@ -288,6 +288,9 @@ > &lt;min_guarantee&gt;65536&lt;/min_guarantee&gt; > &lt;/memtune&gt; > &lt;vcpu cpuset="1-4,^3,6" current="1"&gt;2&lt;/vcpu&gt; > +&lt;numatune&gt; > +&lt;membind nodeset="1,2,!3-6"&gt; > +&lt;/numatune&gt; I don't think we should be creating a new<numatune> element here since it is not actually covering all aspects of NUMA tuning. We already have CPU NUMA pinning in the separate<vcpu> element. NUMA memory pinning should likely be either in the<memtune> or<memoryBacking> elements, probably the latter.

Also, it is not very nice to use a different syntax for negation for the VCPU specification, vs memory node specification "^3" vs "!3"

Looking to the future, we may want to consider how we'd allow host NUMA mapping on a fine grained basis, per guest NUMA node. eg It is possible with QEMU to actually define a guest visible NUMA topology for the virtual CPUs and memory using -numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node] We don't support that yet, which is something we ought to do. At which point you probably also want to be ale to map guest NUMA nodes to host NUMA nodes.