[FLINK-10185] Make ZooKeeperStateHandleStore#releaseAndTryRemove synchronous

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4.2, 1.5.2, 1.6.0, 1.7.0
• Fix Version/s: 1.4.3, 1.5.4, 1.6.1, 1.7.0
• Component/s: Runtime / Coordination
• Labels: pull-request-available
• Assignee: Till Rohrmann
• Reporter: Till Rohrmann
• Created: 20/Aug/18 22:24
• Updated: 12/Sep/18 14:51
• Resolved: 12/Sep/18 14:51

Description

The ZooKeeperStateHandleStore#releaseAndTryRemove method executes parts of its logic synchronously (retrieving the state handle and unlocking the ZNode) and others asynchronously (removing the ZNode). Moreover, the method takes a parameter which is used to execute some logic in case of a successful removal. This was done in order to execute a potentially blocking state discard operation in a different thread.

I think this can be simplified by executing all logic in the same thread and running the callback after having called ZooKeeperStateHandleStore#releaseAndTryRemove. Moreover, if this operation needs to be not blocking one could use a different thread to call into this method.

Issue Links

• links to: GitHub Pull Request #6586