Review request (S) 7195557 NPG: Unexpected number of memory pools

Jon Masamitsu jon.masamitsu at
Thu Sep 6 15:05:44 UTC 2012


Does the code in
happen to work if perm is the last memory pool
in the list and the test

  139                 if (result.size() == numMemoryPools) {
  140                     break;
  141                 }

exits the loop having never seen perm (so not incrementing


On 09/05/12 23:54, Mikael Gerdin wrote:
> Somehow serviceability-dev was dropped from the CC list.
> I uploaded a new webrev since I thought Bengt had a point about being 
> consistent.
> We talked about where to integrate the fix during the perm gen removal 
> meeting and decided that we'd like to push this through jdk8/tl/jdk
> since we're not in a rush for the bug fix, it's already marked as a 
> known failure.
> Can someone from the jdk8 project please Review this fix?
> Thanks
> /Mikael
> On 2012-09-05 12:38, Mikael Gerdin wrote:
>> Bengt,
>> On 2012-09-05 10:52, Bengt Rutisson wrote:
>>> Hi Mikael,
>>> I think this looks good.
>>> One minor thing. You kind of solved the same problem in two different
>>> ways. In you reduce the expected number
>>> and then increase it if you find a perm gen pool. In
>>> MemoryMXBean/ you left the expected value unchanged and
>>> only reduce it if we do not find a perm gen pool.
>>> I think it would be cleaner to use the same approach for both tests and
>>> I think I prefer the way you did it in
>>> since the "normal" case from now on should be that there is no perm 
>>> gen.
>> Good point, I agree that it looks strange, I've updated the MemoryTest
>> changes to act in a similar way to CollectionUsageThreshold.
>> I've uploaded a new webrev with the updated version:
>> /Mikael
>>> Bengt
>>> On 2012-09-05 10:13, Mikael Gerdin wrote:
>>>> Hi,
>>>> With the perm gen removal changes the number of memory pools exported
>>>> by the VM has changed. This causes the tests
>>>> java/lang/management/MemoryMXBean/ and
>>>> java/lang/management/MemoryMXBean/ to 
>>>> fail.
>>>> My suggested fix is to modify the tests to work with VMs both with and
>>>> without perm gen memory pools.
>>>> CR link:
>>>> Webrev:
>>>> I'd also like to request that this fix be allowed to be pushed to
>>>> hsx/hotspot-gc/jdk instead of 8-tl/jdk so we can get rid of these test
>>>> failures in the hotspot testing before we integrate perm removal into
>>>> jdk8.
>>>> With that I'll need someone to sponsor the push since I'm not a
>>>> Committer.
>>>> Thanks
>>>> /Mikael

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