[jboss-jira] [JBoss JIRA] Commented: (JBCACHE-794) Eviction Queue hard limit can cause deadlocks

Eviction Queue hard limit can cause deadlocks --------------------------------------------- Key: JBCACHE-794 URL: http://jira.jboss.com/jira/browse/JBCACHE-794 Project: JBoss Cache Issue Type: Bug Security Level: Public(Everyone can see) Affects Versions: 1.4.0.SP1 Reporter: Owen Taylor Assigned To: Manik Surtani Fix For: 2.0.0, 1.4.0.SP2 if the eviction queue fills up, you can get the situation where: - The eviction queue processing task calls evict() which needs to get a write lock on a node - A different thread has a read lock on that node and is blocking to put something into the eviction queue Once this starts happening the evication queue thread is procesing events *very* slowly because it repeatedly stalls while the lock times out, so the queue will stay full. Without digging into the code too much, possible fixes that occur to me include: 1) Don't have a hard limit on the size of the eviction queue, and just warn when it gets too big 2) Use a timeout of 0 when trying to get the write lock to evict a node, after all, if a node is locked when we try to evict it, it probably shouldn't be evicted anyways.