[GitHub] tillrohrmann opened a new pull request #7654: [FLINK-11524] Solve race condition in EmbeddedLeaderService

[GitBox <gi...@apache.org>]

tillrohrmann opened a new pull request #7654: [FLINK-11524] Solve race condition in EmbeddedLeaderService
URL: https://github.com/apache/flink/pull/7654
 
 
   ## What is the purpose of the change
   
   Using the EmbeddedHaServices it could happen that the EmbeddedLeaderService goes into an
   invalid state if two grant leadership operations are executed concurrently.
   
   The problem was that the first operation when confirming the now outdated leader session id
   would set the EmbeddedLeaderElectionService#isLeader field to false as part of the stale
   confirmation message handling. Consequently, all subsequent calls to
   LeaderElectionService#hasLeadership(newLeaderSessionId) would return false even though the
   contender would still have the leadership.
   
   The solution is to not set the EmbeddedLeaderElectionService#isLeader to false if the
   EmbeddedLeaderService encounters a stale confirmation message.
   
   ## Verifying this change
   
   - Added `EmbeddedHaServicesTest#testConcurrentLeadershipOperations`
   
   ## Does this pull request potentially affect one of the following parts:
   
     - Dependencies (does it add or upgrade a dependency): (no)
     - The public API, i.e., is any changed class annotated with `@Public(Evolving)`: (no)
     - The serializers: (no)
     - The runtime per-record code paths (performance sensitive): (no)
     - Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: (yes)
     - The S3 file system connector: (no)
   
   ## Documentation
   
     - Does this pull request introduce a new feature? (no)
     - If yes, how is the feature documented? (not applicable)
   

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services