Public bug reported: In nova-scheduler, we now uses scheduler/host_manager/update_from_compute_node() to update information about a host from a ComputeNode object. At the beginning of this function, we have a few lines of code:
https://github.com/openstack/nova/blob/master/nova/scheduler/host_manager.py#L162-L164 if (self.updated and compute.updated_at and self.updated > compute.updated_at): return here we will not update the information if the local update time is later than compute update time. This is generally correct, since the compute have a periodic task to update the information: https://github.com/openstack/nova/blob/master/nova/compute/manager.py#L6243 but it only updates if the resource have changed: https://github.com/openstack/nova/blob/master/nova/compute/resource_tracker.py#L659 This can lead to inconsistency if the scheduler have consumed(updated) the information but then the compute fail to claim (the periodic task won't update because there are no changes). We can add an time limit as a config to the above mentioned "if" logic, so that if the difference between current time and self.updated time is larger than the limit, we will also update the information from ComputeNode object, and avoid the inconsistency between different services. ** Affects: nova Importance: Undecided Assignee: Zhenyu Zheng (zhengzhenyu) Status: New ** Changed in: nova Assignee: (unassigned) => Zhenyu Zheng (zhengzhenyu) -- 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/1528743 Title: HostState in Scheduler can be incorrect Status in OpenStack Compute (nova): New Bug description: In nova-scheduler, we now uses scheduler/host_manager/update_from_compute_node() to update information about a host from a ComputeNode object. At the beginning of this function, we have a few lines of code: https://github.com/openstack/nova/blob/master/nova/scheduler/host_manager.py#L162-L164 if (self.updated and compute.updated_at and self.updated > compute.updated_at): return here we will not update the information if the local update time is later than compute update time. This is generally correct, since the compute have a periodic task to update the information: https://github.com/openstack/nova/blob/master/nova/compute/manager.py#L6243 but it only updates if the resource have changed: https://github.com/openstack/nova/blob/master/nova/compute/resource_tracker.py#L659 This can lead to inconsistency if the scheduler have consumed(updated) the information but then the compute fail to claim (the periodic task won't update because there are no changes). We can add an time limit as a config to the above mentioned "if" logic, so that if the difference between current time and self.updated time is larger than the limit, we will also update the information from ComputeNode object, and avoid the inconsistency between different services. To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1528743/+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
