Open Radar

 
23-Sep-2011 02:49 AM Thierry Monney:
'AtomicIntegerArray.java' was successfully uploaded

23-Sep-2011 02:49 AM Thierry Monney:
Summary:

The attached JUnit test case systematically hangs when run with the current OSX Lion Java VM (1.6.0_26-b03-383-11A511) and JIT compilation enabled.

Steps to Reproduce:

Compile the attached source files with the command
> javac *.java

Run with
> java -cp . AtomicIntegerArrayTest

Expected Results:

The program ends normally with the following output:
> Running test
> Test done

Actual Results:

The program hangs with the following output:
> Running test

At this point, the process freezes and cannot even be killed with Ctrl-C. One has to "kill -9" it. It is also impossible to run it in debug mode, e.g. in Eclipse, or to get a thread dump with jstack or attach to the process with JVisualVM.

Regression:

The program terminates normally when the SIZE constant is set to a smaller number (on my machine, 10000 runs fine but 30000 hangs).
The program also runs fine with greater numbers if JIT is disabled, running it with the command
> java -cp . -Djava.compiler=NONE AtomicIntegerArrayTest
It also runs normally with the same JVM version on Windows 7 and with prior JVM versions on OS X Lion (tested with 1.4.2_21-b01-324 and 1.5.0_19-b02-304).

Notes:

The problem is most likely related to JIT compilation for the following reasons:
- Normal Java diagnostic tools are useless, which indicates the VM itself may be corrupted
- The program runs fine with smaller numbers, probably because JIT has not run yet
- The program runs fine when JIT is disabled




23-Sep-2011 02:50 AM Thierry Monney:
'AtomicIntegerArrayTest.java' was successfully uploaded

23-Sep-2011 03:04 PM Thierry Monney:
Actually the test case does not use JUnit, but the point remains the same.