Java deadlock when insert in t1 and find in t2 when using IBM JVM 1.5.0

• Key: OPENJPA-98
• Type: Bug
• Status: Closed
• Resolution: Fixed
• Priority: Major
• Assignee: Kevin Sutter
• Reporter: Vlad Tatavu
• Fix Version/s: 0.9.7

Environment

OpenJPA:
0.9.6

Java:
java version "1.5.0"
Java(TM) 2 Runtime Environment, Standard Edition (build pwi32dev-20061002a (SR3)
)
IBM J9 VM (build 2.3, J2RE 1.5.0 IBM J9 2.3 Windows XP x86-32 j9vmwi3223-2006100
1 (JIT enabled)
J9VM - 20060915_08260_lHdSMR
JIT - 20060908_1811_r8
GC - 20060906_AA)
JCL - 20061002

DB:
Derby 10.2.1.6

Description

I have a simple test program that uses OpenJPA 0.9.6 to insert an object into a db in one transaction (t1) and retrieve it in another transaction (t2). The program hangs in 30-50% of the executions right before the call to entitymanager.find() (used to retrieve the object in t2). I'm using OpenJPA runtime enhancement.


By looking at the JVM dump, I can see the following deadlock:
1LKDEADLOCK Deadlock detected !!!
NULL ---------------------
NULL
2LKDEADLOCKTHR Thread "main" (0x0015EC00)
3LKDEADLOCKWTR is waiting for:
4LKDEADLOCKMON sys_mon_t:0x41E40548 infl_mon_t: 0x41E40588:
4LKDEADLOCKOBJ java/lang/Object@00D41010/00D4101C:
3LKDEADLOCKOWN which is owned by:
2LKDEADLOCKTHR Thread "Finalizer thread" (0x41B36200)
3LKDEADLOCKWTR which is waiting for:
4LKDEADLOCKMON sys_mon_t:0x0035CD38 infl_mon_t: 0x0035CD78:
4LKDEADLOCKOBJ sun/misc/Launcher$AppClassLoader@00D4E5B0/00D4E5BC:
3LKDEADLOCKOWN which is owned by:
2LKDEADLOCKTHR Thread "main" (0x0015EC00)