RFR(S) 8207765: HeapMonitorIntervalRateTest fails with ZGC

[serguei.spitsyn at oracle.com]

Thanks a lot, Alex!

Jc,

Could you please send me a patch for push?

Thanks,
Serguei

On 7/19/18 17:06, Alex Menkov wrote:
> Looks good.
>
> --alex
>
> On 07/19/2018 14:52, JC Beyler wrote:
>> Hi Serguei,
>>
>> Done here:
>> http://cr.openjdk.java.net/~jcbeyler/8207765/webrev.01/ 
>> <http://cr.openjdk.java.net/%7Ejcbeyler/8207765/webrev.01/>
>>
>> I added:
>>
>> + // Calculate the size of a 1-element array in order to assess 
>> average sampling interval
>> + // via the HeapMonitorStatIntervalTest. This is needed because 
>> various GCs could add
>> + // extra memory to arrays.
>> + // This is done by allocating a 1-element array and then looking in 
>> the heap monitoring
>> + // samples for the average size of objects collected.
>>
>>
>> Let me know what you think and then I need one more review to prepare 
>> the patch :-)
>>
>> Thanks all!
>> Jc
>>
>> On Thu, Jul 19, 2018 at 2:33 PM serguei.spitsyn at oracle.com 
>> <mailto:serguei.spitsyn at oracle.com> <serguei.spitsyn at oracle.com 
>> <mailto:serguei.spitsyn at oracle.com>> wrote:
>>
>>     Hi Jc,
>>
>>     The fix looks good to me.
>>     Just minor comments.
>>
>> http://cr.openjdk.java.net/%7Ejcbeyler/8207765/webrev.00/test/hotspot/jtreg/serviceability/jvmti/HeapMonitor/MyPackage/HeapMonitor.java.frames.html
>>
>>     108 public static void calculateAverageOneElementSize() {
>>
>>        Could you, please, add a comment before
>>     calculateAverageOneElementSize method
>>        explaining shortly why it is needed and what it is doing?
>>        Otherwise, it is not easy to understand this code from scratch.
>>
>>     Thanks,
>>     Serguei
>>
>>
>>     On 7/19/18 10:08, JC Beyler wrote:
>>>     I forgot to put the link:
>>>     https://bugs.openjdk.java.net/browse/JDK-8207763
>>>
>>>     It got renamed in jdk11 via:
>>>     http://hg.openjdk.java.net/jdk/jdk11/rev/1edcf36fe15f
>>>
>>>     Thanks!
>>>     Jc
>>>
>>>     On Thu, Jul 19, 2018 at 10:07 AM JC Beyler <jcbeyler at google.com
>>>     <mailto:jcbeyler at google.com>> wrote:
>>>
>>>         Hi Dan,
>>>
>>>
>>> serviceability/jvmti/HeapMonitor/MyPackage/HeapMonitorStatRateTest.java
>>>         became
>>> serviceability/jvmti/HeapMonitor/MyPackage/HeapMonitorStatIntervalTest.java,
>>>         when we updated the spec and said "rate" was the wrong word.
>>>
>>>         So yes, it fixes both since at some point all branches should
>>>         see that the StatRate test becomes renamed into the
>>>         StatInterval test. Does that make sense?
>>>
>>>         Thanks!
>>>         Jc
>>>
>>>
>>>         On Thu, Jul 19, 2018 at 9:45 AM Daniel D. Daugherty
>>>         <daniel.daugherty at oracle.com
>>>         <mailto:daniel.daugherty at oracle.com>> wrote:
>>>
>>>             JDK-8207765 covers two different tests as of yesterday:
>>>
>>> serviceability/jvmti/HeapMonitor/MyPackage/HeapMonitorStatRateTest.java
>>>
>>>             and
>>>
>>> serviceability/jvmti/HeapMonitor/MyPackage/HeapMonitorStatIntervalTest.java
>>>
>>>             I updated it to add a similar failure mode sighting for
>>>             HeapMonitorStatIntervalTest.java
>>>
>>>
>>>             Does your fix address both test failures?
>>>
>>>             Dan
>>>
>>>
>>>             On 7/19/18 12:39 PM, JC Beyler wrote:
>>>>             Hi all,
>>>>
>>>>             Could I have a few reviews of:
>>>> http://cr.openjdk.java.net/~jcbeyler/8207765/webrev.00/
>>>> <http://cr.openjdk.java.net/%7Ejcbeyler/8207765/webrev.00/>
>>>>
>>>>             The  test assumed the size of a 1-element array but ZGC
>>>>             changes that assumption. The test now first allocates a
>>>>             bit of memory and gets the average size of the samples
>>>>             before assuming the size. This works with/without ZGC.
>>>>
>>>>             Webrev:
>>>> http://cr.openjdk.java.net/~jcbeyler/8207765/webrev.00/
>>>> <http://cr.openjdk.java.net/%7Ejcbeyler/8207765/webrev.00/>
>>>>             Bug: https://bugs.openjdk.java.net/browse/JDK-8207765
>>>>
>>>>             Thanks!
>>>>             Jc
>>>
>>>
>>>
>>>         --
>>>         Thanks,
>>>         Jc
>>>
>>>
>>>
>>>     --
>>>     Thanks,
>>>     Jc
>>
>>
>>
>> -- 
>>
>> Thanks,
>> Jc