RFR: 8129590: TestShrinkDefragmentedHeap.java runs out of memory

Stefan Johansson stefan.johansson at oracle.com
Wed Jul 1 14:36:16 UTC 2015

Thanks for the reviews Jesper and Thomas,

I will add the bug id and push right away.


On 2015-07-01 16:37, Thomas Schatzl wrote:
> Hi Stefan,
> On Wed, 2015-07-01 at 15:51 +0200, Stefan Johansson wrote:
>> Hi,
>> Please review this test-fix to avoid:
>> https://bugs.openjdk.java.net/browse/JDK-8129590
>> Webrev:
>> http://cr.openjdk.java.net/~sjohanss/8129590/hotspot.00/
>> Summary:
>> The test specified the initial heap size and the young generation size
>> but not the maximum heap size. It needs more memory than the initial
>> heap size and in most cases this is not a problem, because the heap can
>> be expanded. But on hosts with very little memory it becomes a problem,
>> because the maximum heap size gets limited to the same size as the
>> initial heap size.
>> A simple fix for the issue is to set the the maximum heap size to
>> something a little larger than the initial heap size to make sure the
>> expansion is possible. This might come with other problems if the host
>> can't support the needed heap size, but in such cases I think we should
>> avoid running this test.
>> Testing:
>> * Verified fix on failing host.
>> * Reproduced failure locally by setting small Xmx and verified that
>> making it larger fixes the issue.
>    looks good. Could you add this bug id to the @bug line?
> Thomas

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