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[sean mooney <smooney@xxxxxxxxxx>]

** Changed in: nova
       Status: In Progress => Won't Fix

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https://bugs.launchpad.net/bugs/1691178

Title:
  virt_type=qemu does not support cpu affinity.

Status in OpenStack Compute (nova):
  Won't Fix

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.

  
  logs
  ====
  http://paste.openstack.org/show/609710/

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