Public bug reported: The function which counts resources using the legacy method involves getting a list of all cell mappings assigned to a specific project:
https://github.com/openstack/nova/blob/575a91ff5be79ac35aef4b61d84c78c693693304/nova/quota.py#L1170-L1209 This code can be very heavy on a database which contains a lot of instances (but not a lot of mappings), potentially scanning millions of rows to gather 1-2 cell mappings. In a single cell environment, it is just extra CPU usage with exactly the same outcome. The [api]/instance_list_per_project_cells was introduced to workaround this: https://github.com/openstack/nova/blob/575a91ff5be79ac35aef4b61d84c78c693693304/nova/compute/instance_list.py#L146-L153 However, the quota code does not implement it which means quota count take a big toll on the database server. We should ideally mirror the same behaviour in the quota code. ** Affects: nova Importance: Undecided Status: New -- 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/1878979 Title: Quota code does not respect [api]/instance_list_per_project_cells Status in OpenStack Compute (nova): New Bug description: The function which counts resources using the legacy method involves getting a list of all cell mappings assigned to a specific project: https://github.com/openstack/nova/blob/575a91ff5be79ac35aef4b61d84c78c693693304/nova/quota.py#L1170-L1209 This code can be very heavy on a database which contains a lot of instances (but not a lot of mappings), potentially scanning millions of rows to gather 1-2 cell mappings. In a single cell environment, it is just extra CPU usage with exactly the same outcome. The [api]/instance_list_per_project_cells was introduced to workaround this: https://github.com/openstack/nova/blob/575a91ff5be79ac35aef4b61d84c78c693693304/nova/compute/instance_list.py#L146-L153 However, the quota code does not implement it which means quota count take a big toll on the database server. We should ideally mirror the same behaviour in the quota code. To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1878979/+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
