[jboss-remoting-issues] [JBoss JIRA] (JBREM-762) Deadlock bug in socket invoker

Deadlock bug in socket invoker ------------------------------ Key: JBREM-762 URL: https://issues.jboss.org/browse/JBREM-762 Project: JBoss Remoting Issue Type: Bug Security Level: Public(Everyone can see) Components: transport Affects Versions: 1.4.6.GA Environment: JBoss 4.0.4 EJB 3.0-rc9-patch1 JDK 1.6.0 Reporter: Tim McCune There is a potential thread leak in ServerThread.java that causes ServerThreads to stick around, but to disappear from the thread pool as the accept() thread(s) see it. Eventually, when the # of leaked threads reaches the MaxPoolSize, the system ends up deadlocked and will not accept any more incoming socket connections. I have described the problem in great detail in a forum post and in support case 00016786. I have patched the code, and so far it seems to be working fine and to have fixed the problem. This is what I patched: In ServerThread.java, I wrapped the contents of wakeup() inside of a try/catch, block, with the following code in the catch block: } catch (Exception e) { synchronized (clientpool) { synchronized (threadpool) { clientpool.remove(this); threadpool.add(this); Thread.interrupted(); } } throw e; } This makes sure that the thread is put back into the threadpool when an exception occurs in the createServerSocket() method (this method is doing socket I/O in 1.4.6, and in our case, this socket connection was timing out.).