Re: [libvirt] [RFC PATCH v1 0/4] NUMA Host or Node Partitioning

From: Wim ten Have <wim.ten.have(a)oracle.com&gt; This patch extends guest domain administration by adding a feature that creates a guest with a NUMA layout, also referred to as vNUMA (Virtual NUMA).

The changes brought by this patch series add a new libvirt domain element named <vnuma> that allows for dynamic 'host' or 'node' partitioning of a guest where libvirt inspects the host capabilities and renders a best guest XML design holding a host matching vNUMA topology. <domain> .. <vnuma mode='host|node' distribution='contiguous|siblings|round-robin|interleave'> <memory unit='KiB'>524288</memory> <partition nodeset="1-4,^3" cells="8"/> </vnuma> .. </domain> The content of this <vnuma> element causes libvirt to dynamically partition the guest domain XML into a 'host' or 'node' numa model Under <vnuma mode='host' ... > the guest domain is automatically partitioned according to the "host" capabilities. Under <vnuma mode='node' ... > the guest domain is partitioned according to the nodeset and cells under the vnuma partition subelement. The optional <vnuma> attribute distribution='type' is to indicate the guest numa cell cpus distribution. This distribution='type' can have the following values: - 'contiguous' delivery, under which the cpus enumerate sequentially over the numa defined cells. - 'siblings' cpus are distributed over the numa cells matching the host CPU SMT model. - 'round-robin' cpus are distributed over the numa cells matching the host CPU topology. - 'interleave' cpus are interleaved one at a time over the numa cells. The optional subelement <memory> specifies the memory size reserved for the guest to dimension its <numa> <cell id> size. If no memory is specified, the <vnuma> <memory> setting is acquired from the guest's total memory, <domain> <memory> setting.