[Bug 1542491] Re: Scheduler update_aggregates race causes incorrect aggregate information
** Changed in: nova Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1542491 Title: Scheduler update_aggregates race causes incorrect aggregate information To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1542491/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1542491] Re: Scheduler update_aggregates race causes incorrect aggregate information
your considering make lots of sense, and they are common issues in distributed system, OpenStack use timestamp update method all over the codes like: https://github.com/openstack/nova/blob/master/nova/scheduler/host_manager.py#L185 for your considering: #1, synchronized timing is a basic assumption in distributed system like OS, even it make system prone to going wrong. #2, timestamp is from DB operation, as long as mutli nova-api service operate to same single DB, this won't be a problem. #3, very helpful heads up, the logic will be updating cache as long as DB timestamps = cache timestamps. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1542491 Title: Scheduler update_aggregates race causes incorrect aggregate information To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1542491/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1542491] Re: Scheduler update_aggregates race causes incorrect aggregate information
propose solution: pass DB operation timestamp to scheduler, set it as scheduler update timestamp, if the timestamps of a new update is older than scheduler update timestamp, drop this update. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1542491 Title: Scheduler update_aggregates race causes incorrect aggregate information To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1542491/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1542491] Re: Scheduler update_aggregates race causes incorrect aggregate information
@James Dennis (jtmes) I believe your understanding on #2 is correct. The root cause for this issue is that the aggregate's operation sequence on DB may not exactly as same as on scheduler. for example: operation on DB: 1. add host 2. del host however, on scheduler, if the operation's sequence reversed as: 1. del host 2. add host it will case the DB/scheduler outer-sync. ** Changed in: nova Assignee: (unassigned) => yuntongjin (yuntongjin) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1542491 Title: Scheduler update_aggregates race causes incorrect aggregate information To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1542491/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
