[JCR-2855] Writers blocked forever when waiting on update operations

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.3, 2.2.1
• Fix Version/s: 2.2.4
• Component/s: jackrabbit-core
• Assignee: Jukka Zitting
• Reporter: Yoav Landman
• Created: 27/Dec/10 15:19
• Updated: 17/Feb/11 15:49
• Resolved: 01/Feb/11 15:20

Description

Thread 1 calls Session.save() and has a write lock.

Thread 2 is in XA prepare() and is waiting on thread 1 in FineGrainedISMLocking.acquireWriteLock().

Thread 1's save calls SharedItemStateManager.Update#end() and performs a write-lock downgrade to a read-lock, then (at the end of Update#end()) it calls readLock.release(). FineGrainedISMLocking.ReadLockImpl#release thinks activeWriterId is of the current transation and does not notify any writers (activeWriterId is not being reset on downgrade in what seems to be a related to JCR-2753).
Thread 1 waits forever.