Reviewed: https://review.openstack.org/540258 Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=14f4c502f92b10b669044e5069ac3b3555a42ee0 Submitter: Zuul Branch: master
commit 14f4c502f92b10b669044e5069ac3b3555a42ee0 Author: melanie witt <[email protected]> Date: Fri Feb 2 05:41:20 2018 +0000 Make scheduler.utils.setup_instance_group query all cells To check affinity and anti-affinity policies for scheduling instances, we use the RequestSpec.instance_group.hosts field to check the hosts that have group members on them. Access of the 'hosts' field calls InstanceGroup.get_hosts during a lazy-load and get_hosts does a query for all instances that are members of the group and returns their hosts after removing duplicates. The InstanceList query isn't targeting any cells, so it will return [] in a multi-cell environment in both the instance create case and the instance move case. In the move case, we do have a cell-targeted RequestContext when setup_instance_group is called *but* the RequestSpec.instance_group object is queried early in compute/api before we're targeted to a cell, so a call of RequestSpec.instance_group.get_hosts() will result in [] still, even for move operations. This makes setup_instance_group query all cells for instances that are members of the instance group if the RequestContext is untargeted, else it queries the targeted cell for the instances. Closes-Bug: #1746863 Change-Id: Ia5f5a0d75953b1154a8de3e1eaa15f8042e32d77 ** Changed in: nova Status: In Progress => Fix Released -- 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/1746863 Title: scheduler affinity doesn't work with multiple cells Status in OpenStack Compute (nova): Fix Released Status in OpenStack Compute (nova) pike series: Confirmed Status in OpenStack Compute (nova) queens series: Confirmed Status in OpenStack Compute (nova) rocky series: New Bug description: I happened upon this while hacking on my WIP CellDatabases fixture patch. Some of the nova/tests/functional/test_server_group.py tests started failing with multiple cells and I found that it's because there's a database query 'objects.InstanceList.get_by_filters' for all instances who are members of the server group to do the affinity check. The query for instances doesn't check all cells, so it fails to return any hosts that group members are currently on. This makes the ServerGroup[Anti|]AffinityFilter a no-op for multiple cells. Affinity is checked again via the late-affinity check in compute, but compute is using the same InstanceGroup.get_hosts method and will only find group member's hosts that are in its cell. This is the code that populates the RequestSpec.instance_group.hosts via a lazy-load on first access: nova/objects/instance_group.py: def obj_load_attr(self, attrname): ... self.hosts = self.get_hosts() self.obj_reset_changes(['hosts']) ... @base.remotable def get_hosts(self, exclude=None): """Get a list of hosts for non-deleted instances in the group This method allows you to get a list of the hosts where instances in this group are currently running. There's also an option to exclude certain instance UUIDs from this calculation. """ filter_uuids = self.members if exclude: filter_uuids = set(filter_uuids) - set(exclude) filters = {'uuid': filter_uuids, 'deleted': False} instances = objects.InstanceList.get_by_filters(self._context, filters=filters) return list(set([instance.host for instance in instances if instance.host])) To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1746863/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
