[jboss-user] [JBoss Seam] - Critical bug with WebSphere

[dmitriy.lapko]

Environment: 
IMB WebSphere 6.1.0.11

D:\Program Files\IBM\WebSphere61\AppServer\java\jre\bin>java.exe  -version
java version "1.5.0"
Java(TM) 2 Runtime Environment, Standard Edition (build pwi32devifx-20070608 (SR5+IY99712))
IBM J9 VM (build 2.3, J2RE 1.5.0 IBM J9 2.3 Windows XP x86-32 j9vmwi3223-20070426 (JIT enabled)
J9VM - 20070420_12448_lHdSMR
JIT  - 20070419_1806_r8
GC   - 200704_19)
JCL  - 20070608

Application has some JavaBeans in Session scope. After some crazy stress tests it hangs.

Reason - ReentranceLock in J9 can work in infinite loop. Description of similar bug in Sun JVM - http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6241823

The worst thing - the whole web server hangs and 100% uses processor. Possible way to avoid it - don't set to true

 private ReentrantLock lock = new ReentrantLock(true);

in SynchronizationInterceptor.

How to reproduce bug in WebSphere - run next code: 

  |         Semaphore sem = new Semaphore(0,true);
  |         System.out.println(sem.tryAcquire(100,TimeUnit.MILLISECONDS));
  |         System.out.println(sem.tryAcquire(100,TimeUnit.MILLISECONDS));
  |         System.out.println("OK!");

In Sun JVM it works ok, in IBM J9 - hangs.

Should I post a JIRA issue?

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