[OPENDJ-6377] Replication replay: issues with ReplaySynchronizer - ForgeRock JIRA

During the code review for ~~OPENDJ-6325~~, a few problems became apparent with the ReplaySynchronizer:

In UpdateReplayThreadPool.ReplayThread.run(), when the thread exits the loop, because of shutdown, ReplaySynchronizer.notifyAllReplaysDone() is never called while it looks like it should.
- Risk: Replica listener threads remain blocked - will prevent the server from stopping
In that case, this will unlock the replica listener thread, which will end up calling UpdateReplayThreadPool.offer(), which will throw a IndexOutOfBoundsException because updateQueues has been cleared
Another issue with UpdateReplayThreadPool.ReplaySynchronizer.waitForAllReplaysDone() is the case of spurious wake-ups: when Semaphore.acquire(int) throws InterruptedException (because of spurious wake-up) it will incorrectly execute the following code in the finally block:stopTheWorld = false;

There may be some other concurrency issue as well.
This issue can be considered to be fixed when all identified concurreny issues are addressed.

is backported by

OPENDJ-6611 Backport OPENDJ-6377: Replication replay: issues with ReplaySynchronizer

OPENDJ-6953 Backport OPENDJ-6377: Replication replay: issues with ReplaySynchronizer

OPENDJ-6998 Backport OPENDJ-6377: Replication replay: issues with ReplaySynchronizer

is caused by

OPENDJ-6325 Replication: modifying an entry leaf with a new superior is not replicated

is related to

OPENDJ-6416 Replication replay: consider blocking the updates to replay only by domain instead of globally

relates to

OPENDJ-5498 Deadlock with Replay threads "stop the world" mechanism when there are multiple domains

(1 relates to)