[jboss-jira] [JBoss JIRA] Closed: (JBAS-2583) Potential for runaway allocation of Connection objects

Potential for runaway allocation of Connection objects ------------------------------------------------------ Key: JBAS-2583 URL: http://jira.jboss.com/jira/browse/JBAS-2583 Project: JBoss Application Server Issue Type: Feature Request Security Level: Public(Everyone can see) Components: JMS service Affects Versions: JBossAS-4.0.3 SP1 Reporter: Natalia Kowalczyk org.jboss.mq.Connection class uses a singleton EDU.oswego.cs.dl.util.concurrent.ClockDaemon to handle pinging of open connections. When connection is opened a ping task is scheduled by inserting into EDU.oswego.cs.dl.util.concurrent.Heap structure maintained internally by ClockDaemon. When connection is closed, its ping task is marked as canceled and subsequently extracted from the Heap by a single thread maintained internally by ClockDaemon. Inserting into Heap structure can be performed by many threads (as part of opening a connection) but extracting is only done by a single thread (in ClockDeamon). As Heap.extract() is a little slower then Heap.insert(), under sufficient system load, ClockDeamon thread may fall behind in its job of removing canceled ping tasks (corresponding to closed connections). If the load on a system persists sufficiently long, JVM will run out of memory because of the canceled ping tasks that ClockDaemon can't extract fast enough.