Public bug reported:
Description
===========
QEMU support a number of different backends for code generation.
Qemu with the TCG(tiny code generator) backend does not support
cpu affinity. the TCG backened is used when the nova
virt_type is set to qemu.
Currently by default when we
request a numa topology nova generates vcpupin elements
that confine the guest vcpus to float only across
the core that are associated with a numa node.
Currently by default when we request hugepage memory
nova implictly generates a numa topology of 1 if no
numa topology is specified.
as a result of the above behavior it is not possible
to spawn a guest a guest with a numa topology or
hugepage memory backing on non kvm/xen acclerated qemu backends
as qemu with the TCG backend does not support cpu affinity.
Steps to reproduce
==================
- deploy nova as normal and set virt_type=qemu in nova.conf.
- set hw:numa_nodes=1 or hw:mem_page_size=large in the nova flavor.
- boot an instance with this modified flavor.
Expected result
===============
vm starts with a virtual numa topology of 1 numa node(hw:numa_nodes=1)
or with hugepage backed memory (hw:mem_page_size=large)
Actual result
=============
nova reports libvirt error that cpu affinity is not support by TCG
backend.
** Affects: nova
Importance: Undecided
Assignee: sean mooney (sean-k-mooney)
Status: New
** Changed in: nova
Assignee: (unassigned) => sean mooney (sean-k-mooney)
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https://bugs.launchpad.net/bugs/1691178
Title:
virt_type=qemu does not support cpu affinity.
Status in OpenStack Compute (nova):
New
Bug description:
Description
===========
QEMU support a number of different backends for code generation.
Qemu with the TCG(tiny code generator) backend does not support
cpu affinity. the TCG backened is used when the nova
virt_type is set to qemu.
Currently by default when we
request a numa topology nova generates vcpupin elements
that confine the guest vcpus to float only across
the core that are associated with a numa node.
Currently by default when we request hugepage memory
nova implictly generates a numa topology of 1 if no
numa topology is specified.
as a result of the above behavior it is not possible
to spawn a guest a guest with a numa topology or
hugepage memory backing on non kvm/xen acclerated qemu backends
as qemu with the TCG backend does not support cpu affinity.
Steps to reproduce
==================
- deploy nova as normal and set virt_type=qemu in nova.conf.
- set hw:numa_nodes=1 or hw:mem_page_size=large in the nova flavor.
- boot an instance with this modified flavor.
Expected result
===============
vm starts with a virtual numa topology of 1 numa node(hw:numa_nodes=1)
or with hugepage backed memory (hw:mem_page_size=large)
Actual result
=============
nova reports libvirt error that cpu affinity is not support by TCG
backend.
To manage notifications about this bug go to:
https://bugs.launchpad.net/nova/+bug/1691178/+subscriptions
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