Reviewed: https://review.openstack.org/339715 Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=0bf9c91bb7a98d0ba8a0565d555560936262e635 Submitter: Zuul Branch: master
commit 0bf9c91bb7a98d0ba8a0565d555560936262e635 Author: Chris Friesen <[email protected]> Date: Fri Oct 28 03:57:37 2016 -0600 Filter out stale migrations in resource audit When doing the resource audit there is a subtle bug in the current code. The problem arises if: 1) You have one or more stale migrations which didn't complete properly that involve the current compute node. 2) The instance from the uncompleted migration is currently doing a resize/migration that does not involve the current compute node. When this happens, _update_usage_from_migrations() will be passed in the stale migration, and the instance is in fact in a resize state, so the current compute node will erroneously account for the instance. The fix is to check that the instance migration ID matches the ID of the migration being analyzed. This will work because in the case of the stale migration we will have hit the error case in _pair_instances_to_migrations(), and so the instance will be lazy-loaded from the DB, ensuring that its migration ID is up-to-date. If the IDs don't match, we'll set the migration status to "error" (to prevent retrieving that migration the next time) and skip updating the usage from the stale migration. Closes-Bug: #1600304 Change-Id: I6f5ad01cb1392db3e2b71e322c5be353de9071a2 ** 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/1600304 Title: _update_usage_from_migrations() can end up processing stale migrations Status in OpenStack Compute (nova): Fix Released Bug description: I recently found a bug in Mitaka, and it appears to be still present in master. I was testing a separate patch by doing resizes, and bugs in my code had resulted in a number of incomplete resizes involving compute-1. I then did a resize from compute-0 to compute-0, and saw compute-1's resource usage go up when it ran the resource audit. This got me curious, so I went digging and discovered a gap in the current resource audit logic. The problem arises if: 1) You have one or more stale migrations which didn't complete properly that involve the current compute node. 2) The instance from the uncompleted migration is currently doing a resize/migration that does not involve the current compute node. When this happens, _update_usage_from_migrations() will be passed in the stale migration, and since the instance is in fact in a resize state, the current compute node will erroneously account for the instance. (Even though the instance isn't doing anything involving the current compute node.) The fix is to check that the instance migration ID matches the ID of the migration being analyzed. This will work because in the case of the stale migration we will have hit the error case in _pair_instances_to_migrations(), and so the instance will be lazy-loaded from the DB, ensuring that its migration ID is up-to-date. To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1600304/+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
