PING: RFR: JDK-8153333: [REDO] STW phases at Concurrent GC should count in PerfCounter

Yasumasa Suenaga yasuenag at gmail.com
Tue Feb 6 12:52:00 UTC 2018


Hi Stefan,

On 2018/02/06 21:44, Stefan Johansson wrote:
> Hi,
> 
> On 2018-02-06 06:30, Yasumasa Suenaga wrote:
>> Hi Stefan,
>>
>> I've got another report from submit repo, and it includes one error on OS X.
>> Can you share it?
>>
>> http://java.se.oracle.com:10065/mdash/jobs/mach5-one-ysuenaga-JDK-8153333-20180206-0355-10435
> This is a known issue, Robin W is working on a fix as we speak:
> https://bugs.openjdk.java.net/browse/JDK-8193308

Thanks!

So could you review and sponsor for this change?


Yasumasa


> Stefan
> 
>>
>> I've tested this change (webrev.06) on Linux x64.
>>
>>
>> Thanks,
>>
>> Yasumasa
>>
>>
>> 2018-02-06 14:10 GMT+09:00 Yasumasa Suenaga <yasuenag at gmail.com>:
>>> Hi Stefan,
>>>
>>>> I agree, for G1 this should not be controlled. Maybe I was a bit unclear, I
>>>> was wondering why we want to control it for CMS.
>>> I said to remove -XX:EnableConcGCPerfCounter in two years ago. I've
>>> missed it :-)
>>>
>>>    http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-March/017125.html
>>>
>>> So I uploaded new webrev. This change includes copyright year updates.
>>>
>>>    http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.06/
>>>
>>> This change passes all tests on submit repo, and
>>> :hotspot_serviceability :jdk_tools tests on my laptop.
>>>
>>>    http://java.se.oracle.com:10065/mdash/jobs/mach5-one-ysuenaga-JDK-8153333-20180206-0222-10428
>>>
>>>
>>>> If we do the change for CMS, we should
>>>> probably also do a CSR, but that should be fairly straight forward.
>>> What should I do to get CSR approve?
>>>
>>>
>>> Thanks,
>>>
>>> Yasumasa
>>>
>>>
>>> 2018-02-06 0:33 GMT+09:00 Stefan Johansson <stefan.johansson at oracle.com>:
>>>>
>>>> On 2018-02-03 06:40, Yasumasa Suenaga wrote:
>>>>> On 2018/02/02 23:38, Stefan Johansson wrote:
>>>>>> Hi Yasumasa,
>>>>>>
>>>>>> The changes doesn't apply clean on the latest jdk/hs, can you provide an
>>>>>> updated webrev?
>>>>>
>>>>> I uploaded webrev for jdk-hs:
>>>>>    cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.05/
>>>>>
>>>> Thanks, I've kicked off a testing job now to verify nothing unexpected
>>>> fails.
>>>>>
>>>>>> The testing done by the submit repo doesn't cover the tests you have
>>>>>> update so I plan to take the change for a spin and make sure the correct
>>>>>> tests are run and verified in Mach 5.
>>>>>
>>>>> I've also tested hotspot/jtreg/:hotspot_serviceability and jdk/:jdk_tools
>>>>> on my laptop.
>>>>> I did not see any errors / failures which are related to this change.
>>>> I also ran some local tests on this and it looks good.
>>>>>
>>>>>
>>>>>> Also a question about the change. Why do we need a special flag for CMS?
>>>>>> I see that the original bug report refers to the flag as being a way to turn
>>>>>> on and off the feature but the current implementation only consider the flag
>>>>>> for CMS.
>>>>>
>>>>>
>>>>> http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-March/016774.html
>>>>>
>>>>> Originally, STW phases (Remark and Cleanup) at G1 are not counted in jstat
>>>>> FGC column.
>>>>> So I think we need not to control the behavior of PerfCounter for G1.
>>>>>
>>>> I agree, for G1 this should not be controlled. Maybe I was a bit unclear, I
>>>> was wondering why we want to control it for CMS. I think either we should
>>>> change the behavior without guarding it by a flag or just skip updating CMS
>>>> (and leave the pauses in FGC). If we do the change for CMS, we should
>>>> probably also do a CSR, but that should be fairly straight forward.
>>>>
>>>> I also found the old review thread where Jon M had the same comment
>>>> (removing the flag) and it looks like all agreed on that:
>>>> http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-March/017118.html
>>>>
>>>> Thanks,
>>>> Stefan
>>>>
>>>>
>>>>> Thanks,
>>>>>
>>>>> Yasumasa
>>>>>
>>>>>
>>>>>> Thanks,
>>>>>> Stefan
>>>>>>
>>>>>> On 2018-02-01 14:58, Yasumasa Suenaga wrote:
>>>>>>> PING: Could you review and sponsor it?
>>>>>>>
>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.04/
>>>>>>>
>>>>>>> This change has been passed Mach 5 via submit repo:
>>>>>>>
>>>>>>> http://java.se.oracle.com:10065/mdash/jobs/mach5-one-ysuenaga-JDK-8153333-20180201-0805-10101
>>>>>>>
>>>>>>>
>>>>>>> Thanks,
>>>>>>>
>>>>>>> Yasumasa
>>>>>>>
>>>>>>>
>>>>>>> On 2017/11/01 22:02, Yasumasa Suenaga wrote:
>>>>>>>> PING: Could you review and sponsor it?
>>>>>>>>
>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.04/
>>>>>>>>
>>>>>>>> Also I need JPRT results of this change.
>>>>>>>> Could you cooperate?
>>>>>>>>
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>>
>>>>>>>> Yasumasa
>>>>>>>>
>>>>>>>>
>>>>>>>> On 2017/09/27 0:08, Yasumasa Suenaga wrote:
>>>>>>>>> Hi all,
>>>>>>>>>
>>>>>>>>> I uploaded new webrev to be adapted to jdk10/hs:
>>>>>>>>>
>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.04/
>>>>>>>>>
>>>>>>>>> I want to check this patch via JPRT, but I cannot access it.
>>>>>>>>> Could you cooperate?
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>>
>>>>>>>>> yasumasa
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On 2017/09/21 7:46, Yasumasa Suenaga wrote:
>>>>>>>>>> PING:
>>>>>>>>>>
>>>>>>>>>> Have you checked this issue?
>>>>>>>>>>
>>>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.03/hotspot/
>>>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.03/jdk/
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Yasumasa
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On 2017/07/01 23:44, Yasumasa Suenaga wrote:
>>>>>>>>>>> PING:
>>>>>>>>>>>
>>>>>>>>>>> Have you checked this issue?
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Yasumasa
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> On 2017/06/14 13:22, Yasumasa Suenaga wrote:
>>>>>>>>>>>> Hi all,
>>>>>>>>>>>>
>>>>>>>>>>>> I changed PerfCounter to show CGC STW phase in jstat in
>>>>>>>>>>>> JDK-8151674.
>>>>>>>>>>>> However, it occurred several jtreg test failure, so it was
>>>>>>>>>>>> back-outed.
>>>>>>>>>>>>
>>>>>>>>>>>> I want to resume to work for this issue.
>>>>>>>>>>>>
>>>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.03/hotspot/
>>>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8153333/webrev.03/jdk/
>>>>>>>>>>>>
>>>>>>>>>>>> These changes are work fine on jtreg test as below:
>>>>>>>>>>>>
>>>>>>>>>>>>     hotspot/test/serviceability/tmtools/jstat
>>>>>>>>>>>>     jdk/test/sun/tools
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Since JDK 9, default GC algorithm is set to G1.
>>>>>>>>>>>> So I think this change is useful to watch GC behavior through
>>>>>>>>>>>> jstat.
>>>>>>>>>>>>
>>>>>>>>>>>> I cannot access JPRT. Could you help?
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>
>>>>>>>>>>>> Yasumasa
>>>>>>>>>>>>
> 


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