8225200: runtime/memory/RunUnitTestsConcurrently.java has a memory leak - push to jdk13?

[Daniel D. Daugherty]

The subject has the following bug ID: 8225200

     JDK-8225200 assert(vs.actual_committed_size() >= commit_size) failed

and a synopsis from a different bug:

     JDK-8227041 runtime/memory/RunUnitTestsConcurrently.java has a 
memory leak

Please clarify which you would like to backport...

Dan



On 7/17/19 10:10 AM, Langer, Christoph wrote:
> Hi,
>
> as we're running into this issue in our nightly test environment, I would be very interested to bring this thing to jdk13. As per RDP rules (https://openjdk.java.net/jeps/3) , we are currently transitioning from RDP1 to RDP2. But in both phases, it is allowed to push test fixes. So, would you say this is a test fix and can be pushed while still adhering to the rules? I'd say yes, but I'd like to get some confirmation (or rejection if I'm wrong...)
>
> That would be the change to push: http://hg.openjdk.java.net/jdk/jdk/rev/8a153a932d0f
>
> Thanks
> Christoph
>
>
>> -----Original Message-----
>> From: hotspot-dev <hotspot-dev-bounces at openjdk.java.net> On Behalf Of
>> Thomas Stüfe
>> Sent: Montag, 1. Juli 2019 21:19
>> To: Coleen Phillmore <coleen.phillimore at oracle.com>
>> Cc: HotSpot Open Source Developers <hotspot-dev at openjdk.java.net>
>> Subject: Re: RFR(xs): 8225200:
>> runtime/memory/RunUnitTestsConcurrently.java has a memory leak
>>
>> Thanks Coleen!
>>
>> On Mon, Jul 1, 2019, 21:14 <coleen.phillimore at oracle.com> wrote:
>>
>>> +1
>>> Thank you for taking care of this!
>>> Coleen
>>>
>>> On 7/1/19 3:07 PM, Thomas Stüfe wrote:
>>>> Thanks Stefan!
>>>>
>>>> On Mon, Jul 1, 2019, 21:06 Stefan Karlsson <stefan.karlsson at oracle.com>
>>>> wrote:
>>>>
>>>>> On 2019-07-01 20:56, Thomas Stüfe wrote:
>>>>>> Hi all,
>>>>>>
>>>>>> may I please have reviews and opinions about the following patch:
>>>>>>
>>>>>> Issue: https://bugs.openjdk.java.net/browse/JDK-8227041
>>>>>> cr:
>>>>>>
>>> http://cr.openjdk.java.net/~stuefe/webrevs/8227041-
>> rununittestsconcurrently-has-a-mem-leak/webrev.00/webrev/index.html
>>>>>> There is a memory leak in test_virtual_space_list_large_chunk(), called
>>>>> as
>>>>>> part of the whitebox tests WB_RunMemoryUnitTests(). In this test
>>>>> metaspace
>>>>>> allocation is tested by rapidly allocating and subsequently leaking a
>>>>>> metachunk of ~512K. This is done by a number of threads in a tight
>> loop
>>>>> for
>>>>>> 15 seconds, which usually makes for 10-20GB rss. Test is usually OOM
>>>>> killed.
>>>>>> This test seems to be often excluded, which makes sense, since this
>>> leak
>>>>>> makes its memory usage difficult to predict.
>>>>>>
>>>>>> It is also earmarked by Oracle for gtest-ification, see 8213269.
>>>>>>
>>>>>> This leak is not easy to fix, among other things because it is not
>>> clear
>>>>>> what it is it wants to test. Meanwhile, time moved on and we have
>> quite
>>>>>> nice gtests to test metaspace allocation (see e.g.
>>>>>> test_metaspace_allocation.cpp) and I rather would run those gtests
>>>>>> concurrently. Which could be a future RFE.
>>>>>>
>>>>>> So I just removed this metaspace related test from
>>>>> WB_RunMemoryUnitTests()
>>>>>> altogether, since to me it does nothing useful. Once you remove the
>>>>> leaking
>>>>>> allocation, not much is left.
>>>>>>
>>>>>> Without this part RunUnitTestsConcurrently test runs smoothly
>> through
>>> its
>>>>>> other parts, and in that form it is still useful.
>>>>>>
>>>>>> What do you think?
>>>>> I think this makes sense and it looks good to me.
>>>>>
>>>>> Thanks,
>>>>> StefanK
>>>>>
>>>>>> Cheers, Thomas
>>>