Public bug reported: During live migration, the setup_networks_on_host neutronv2 API method checks to see if the provided host is different from the existing instance.host and if so, it knows the instance is being migrated and sets the 'migrating_to' attribute to the new host in the ports binding profile:
https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/network/neutronv2/api.py#L351 https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/network/neutronv2/api.py#L322 And then updates the port. That happens in pre_live_migration which runs on the dest host: https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/compute/manager.py#L6007 And it also happens again in post_live_migration_at_destination which runs on the destination host: https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/compute/manager.py#L6382 Since the neutronv2 API code doesn't check to see if the 'migrating_to' attribute is already set: https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/network/neutronv2/api.py#L322 It does a redundant PUT (port update) for no actual change. ** Affects: nova Importance: Low Assignee: Matt Riedemann (mriedem) Status: Triaged ** Tags: live-migration neutron performance -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to OpenStack Compute (nova). https://bugs.launchpad.net/bugs/1758453 Title: Port binding 'migrating_to' attribute needlessly updated in post-live- migration for neutron Status in OpenStack Compute (nova): Triaged Bug description: During live migration, the setup_networks_on_host neutronv2 API method checks to see if the provided host is different from the existing instance.host and if so, it knows the instance is being migrated and sets the 'migrating_to' attribute to the new host in the ports binding profile: https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/network/neutronv2/api.py#L351 https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/network/neutronv2/api.py#L322 And then updates the port. That happens in pre_live_migration which runs on the dest host: https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/compute/manager.py#L6007 And it also happens again in post_live_migration_at_destination which runs on the destination host: https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/compute/manager.py#L6382 Since the neutronv2 API code doesn't check to see if the 'migrating_to' attribute is already set: https://github.com/openstack/nova/blob/55b22a54e65728712670c5dde5a833f5349e5b2f/nova/network/neutronv2/api.py#L322 It does a redundant PUT (port update) for no actual change. To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1758453/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : yahoo-eng-team@lists.launchpad.net Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
