RFR for JDK-7067973: test/java/lang/management/MemoryMXBean/CollectionUsageThreshold.java hanging intermittently

[Eric Wang]

Hi Everyone,

I'm working on the bug https://bugs.openjdk.java.net/browse/JDK-7067973.

It is a test bug as the test doesn't guarantee memory allocated from the 
Old Gen, if the used memory is zero and doesn't cross the threshold, no 
notification is sent, so both the main thread and Checker thread are 
blocked to wait for the GC notification.

so the suggested fix is similar as the fix ResetPeakMemoryUsage.java 
<http://hg.openjdk.java.net/jdk8/tl/jdk/rev/a0896634ab46> to create big 
object to make sure the old gen usage crosses the threshold and run test 
with different GC vmoptions.

Please let me know if you have any comments or suggestions. If you are 
OK with the solution, I'll send a webrev in the next mail.

Thanks,
Eric