openstack-manuals/doc/admin-guide/source/cli_nova_numa_libvirt.rst
Joseph Robinson 2ce5b11b1a [User Guides] Rename Admin-Guide-Cloud to Admin-Guide
This patch changes the name of the Admin-Guide from the Cloud
Admin Guide to the Administrator guide. This affects the
filename in the repository, and references to cloud administrators
within the document texts.

1.) Changing instances of 'cloud administrator'
    to 'administrator'.

2.) Change links from '/admin-guide-cloud/' to
    '/admin-guide/' within the Admin Guide.

3.) Adjust .htaccess file.

Change-Id: I7f21a710e922981aa295afc0616de36fd819b523
Implements: blueprint user-guides-reorganised
2016-04-01 19:50:13 +09:00

1.2 KiB

Consider NUMA topology when booting instances

NUMA topology can exist on both the physical hardware of the host, and the virtual hardware of the instance. OpenStack Compute uses libvirt to tune instances to take advantage of NUMA topologies. The libvirt driver boot process looks at the NUMA topology field of both the instance and the host it is being booted on, and uses that information to generate an appropriate configuration.

If the host is NUMA capable, but the instance has not requested a NUMA topology, Compute attempts to pack the instance into a single cell. If this fails, though, Compute will not continue to try.

If the host is NUMA capable, and the instance has requested a specific NUMA topology, Compute will try to pin the vCPUs of different NUMA cells on the instance to the corresponding NUMA cells on the host. It will also expose the NUMA topology of the instance to the guest OS.

If you want Compute to pin a particular vCPU as part of this process, set the vcpu_pin_set parameter in the nova.conf configuration file. For more information about the vcpu_pin_set parameter, see the Configuration Reference Guide.