RFR: 8170737: Not enough old space utilisation

[Dmitry Fazunenko]

Hi Michail,

new version looks good to me.
Thanks for addressing my comments.

-- Dima

On 26.01.2017 14:00, Michail Chernov wrote:
> Hi,
>
> I updated the webrev according to offline coments from Dmitry Fazunenko.
> GarbageProducerTestBase was renamed to GarbageProducerTest. 
> GcCauseTest02 and GcTest02 now uses GarbageProducerTest directly 
> without inheritance.
>
> http://cr.openjdk.java.net/~mchernov/8170737/webrev.02_to_01/
> http://cr.openjdk.java.net/~mchernov/8170737/webrev.02/
>
> Thanks,
> Michail
>
> On 24/01/2017 17:52, Michail Chernov wrote:
>> Hi Dima,
>>
>> Thanks for your response.
>>
>> Updated webrev:
>> http://cr.openjdk.java.net/~mchernov/8170737/webrev.01/
>>
>> Tests were refactored.
>> There were several problems:
>> 1. Checking of jstat output consistency should not be performed 
>> during GC cycles because it can cause to additional failures. There 
>> is checking in GarbageProducerTestBase.java that during jstat 
>> execution were not any GC cycles. Jstat gets performance counters 
>> values sequentially, so GC cycles should be avoided.
>> 2. New gen size should be limited, because there can be OOME while 
>> eating 70% of heap on some configurations.
>> 3. Tests failed to get expected old gen occupancy because background 
>> VM activity can change real occupancy. Now tests check real heap 
>> occupancy (using MXBean) and compares it with jstat output.
>>
>> The testing is in progress.
>>
>> Thanks,
>> Michail
>>
>> On 13/01/2017 19:55, Dmitry Fazunenko wrote:
>>> Hi Michail,
>>>
>>> GarbageProducer tries to predict at the beginning how many objects 
>>> to allocate later to achieve target memory usage percent.
>>> This way doesn't look like a good idea:
>>> - objects created by libraries (during initialization) may not be 
>>> collected yet
>>> - eatMetaspace() besides allocating metaspace consumes some heap 
>>> space, but this amount is not taken into account.
>>>
>>> Will it make sense to use MXBean for heap as well as for metaspace?
>>>
>>> Thanks,
>>> Dima
>>>
>>> ps: one more nit: "GarbageProducer{" - please insert a space.
>>>
>>> On 13.01.2017 14:56, Michail Chernov wrote:
>>>> Hi,
>>>>
>>>> Could I have a reviews for this change, please?
>>>>
>>>> http://cr.openjdk.java.net/~mchernov/8170737/webrev.00/
>>>> https://bugs.openjdk.java.net/browse/JDK-8170737
>>>>
>>>> Test fails because Runtime.maxMemory() results depends on the heap 
>>>> size shrinking. So need to calculate the expected heap occupation 
>>>> before a garbage allocation. Tests were updated accordingly. Also 
>>>> GcProvokerImpl.java was removed because it was not removed on 
>>>> previous commit by mistake.
>>>> Tested via RBT.
>>>>
>>>> Thanks,
>>>> Michail
>>>
>>>
>>
>>
>