[SAMZA-1348] Run stop() in the StreamProcessor in the same thread as other events.

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Unassigned
• Reporter: Boris Shkolnik
• Created: 28/Jun/17 00:15
• Updated: 01/Aug/17 19:55

Description

stop() should be running in the same thread as other events. Since sometimes it is invoked form the container thread, it may end up running at the same time as another event from ZK.
Even, if one of the first things stop() does is stopping the scheduler, an event still may be running. So the solution would be to call the stop () from JobCoordinator, using the same debouncing thread as every other event. It will do the following:

• Cancel all the currently en-queued tasks. It still may have one task running.
• Schedule itself (stop()) on the same debounce thread.

Note. Since we are using scheduler's thread to run stop(), we won't be able to run scheduler.stop(). But that should be fine, since it is a daemon thread.

Issue Links

• is related to: SAMZA-1064 Standalone Samza with Zookeeper for Coordination
• is related to: SAMZA-1349 Fix stop() sequence in the StreamProcessor