starlingx
/
openstack-armada-app
Code Issues Proposed changes

Skip destination CPU check during live-migration 

OpenStack 2023.1 (Antelope) introduced this issue [1][2] when
live-migrating instances, in which Nova uses getCapabilities() to
determine the host CPU model but use the model from the
domCapabilities for the guest VM using host-model [3].
According to the libvirt maintainers nova should never use
getCapabilities for anything any more.
A solution for this issue is being developed in main branch [4], but
taken as a medium priority since there is a workaround config option
already available [5] to avoid this situation.

Setting "skip_cpu_compare_on_dest" to True will, during live
migration, skip comparing guest CPU with the destination host.
When using QEMU >= 2.9 and libvirt >= 4.4.0, libvirt will do the
correct thing with respect to checking CPU compatibility on the
destination host during live migration.
StarlingX currently delivers QEMU 5.2 and stx-openstack uses a libvirt
on 7.0.0-3, therefore this can be safely used as part of our default
nova configuration updates.

[1] https://bugs.launchpad.net/nova/+bug/2023035
[2] https://bugs.launchpad.net/nova/+bug/2039803
[3] https://review.opendev.org/q/topic:fix_compareCPU_usage
[4] https://review.opendev.org/c/openstack/nova/+/899185
[5] https://docs.openstack.org/nova/latest/configuration/config.html#skip_cpu_compare_on_dest

Closes-bug: 2007303

TEST PLAN:
PASS - Build python3-k8sapp-openstack plugins
PASS - Build stx-openstack application
PASS - Upload/Apply/Remove stx-openstack
PASS - Live-migrate an instance
PASS - Manually reboot a compute node in which
       an instance is running to ensure it is
       correctly evacuated to another compute

Change-Id: Id7a93445af4115ee81b035b4f9dc7a6eb889555b
Signed-off-by: Thales Elero Cervi <thaleselero.cervi@windriver.com>
This commit is contained in:
Thales Elero Cervi 2023-11-13 09:25:40 -03:00
parent 1ded5ebc08
commit c133617339
1 changed files with 9 additions and 0 deletions
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9
python3-k8sapp-openstack/k8sapp_openstack/k8sapp_openstack/helm/nova.py
View File

@ -784,10 +784,19 @@ class NovaHelm(openstack.OpenstackBaseHelm):
'ephemeral_storage': self._get_rbd_ephemeral_storage(),
'admin_keyring': admin_keyring,
},
# NOTE(tcervi): Nova config options reference:
# https://docs.openstack.org/nova/latest/configuration/sample-config.html
# https://docs.openstack.org/nova/latest/configuration/config.html
'nova': {
'libvirt': {
'virt_type': self._get_virt_type(),
},
# NOTE(tcervi): Workaround needed since OpenStack 2023.1
# Can be removed once nova/+bug/2023035 and
# nova/+bug/2039803 are fixed.
'workarounds': {
'skip_cpu_compare_on_dest': True,
},
'vnc': {
'novncproxy_base_url': self._get_novncproxy_base_url(),
},