Hi, Just coming from my curiosity (inline).
On Thu, Apr 14, 2016 at 12:34 AM, Dan Smith <[email protected]> wrote: >> * nova-api should receive an acknowledgement from nova-compute. It is >> unclear to me why today it uses a non-reply mechanism - probably to >> free the worker as fast as it can. > > Yes, wherever possible, we want the API to return immediately and let > the action complete later. Making a wholesale change to blocking calls > from the API to any other service is not a good idea, IMHO. > >> * Change the task_state mechanism to prevent this kind of a stuck >> state to stay in the DB. nova-compute can be the one that writes the >> task_state to the DB, but this is not enough of course, but maybe >> there's another way? > > The task_state being set in the API is our way of limiting/locking the > operation so that if the request is queued for a long time, a user > doesn't reissue the command a bunch of time and add load to the API > and/or jam up the queue with a thousand requests to do the same > operation just because it's taking a while. > >> * nova-api could start a timer for the action to complete. If the >> shelving operation hasn't completed in X seconds, it will clean it >> by itself and rollback\try-again. > > I have wanted to make a change for a while that involves a TTL on > messages, along with a deadline record so that we can know when to retry > or revert things that were in flight. This requires a lot of machinery > to accomplish, and is probably interwoven with the task concept we've > had on the back burner for a while. The complexity of moving nova to > this sort of scheme means that nobody has picked it up as of yet, but > it's certainly in the minds of many of us as something we need to do > before too long. Are you still thinking of this kind of mechanism deployment? We need any kind of RPC handling mechanism at the end of the day. > > --Dan > > __________________________________________________________________________ > OpenStack Development Mailing List (not for usage questions) > Unsubscribe: [email protected]?subject:unsubscribe > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev -- Email: [email protected] GitHub: shinobu-x Blog: Life with Distributed Computational System based on OpenSource __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
