RFR: 8183910: gc/arguments/TestAggressiveHeap.java fails intermittently

[Stefan Johansson]

Hi,

Please review this test change to avoid memory exhaustion during testing.

Issue: https://bugs.openjdk.java.net/browse/JDK-8183910
Webrev: http://cr.openjdk.java.net/~sjohanss/8183910/00

Summary
The option AggressiveHeap sets the heap to half of the physical memory, 
turns on ParallelGC and set a bunch of other options. The test 
TestAggressiveHeap only verifies that Parallel GC was set. With this in 
mind I don't see a good reason for letting this test set the heap size 
so big and cause a lot of problems in our testing environment. The 
suggested fix limits the heap to 128M which is half of what the option 
requires the machine to have. This can of course still cause failures on 
systems with little memory, but the problem is not bigger than today 
since the system must have more than 256M for the test to run.

Testing
Turned off swap on my machine and ran the tests in hotspot/gc/arguments 
with concurrency 10. This always cause a few failures, either in 
TestAggressiveHeap it self of in some other test running concurrently 
that cannot allocate its heap. With the fix, I've run several runs 
without any problems.

Since this is an intermittent issue in our testing environment I haven't 
tried to verify it there but limiting the memory use should really fix 
the problems we see there the same way as it fixed my local problems.

Thanks,
Stefan