[15] RFR 8238633: JVMTI heap walk should consult GC for marking oops

[serguei.spitsyn at oracle.com]

Hi Zhengyu,

It looks okay to me.
The testing you do looks enough for verification.
But I'm not sure about performance testing though.

Thanks,
Serguei


On 2/17/20 6:51 AM, Zhengyu Gu wrote:
> Hi Stefan,
>
> Thanks for the review and suggestions, updated accordingly:
>
> http://cr.openjdk.java.net/~zgu/JDK-8238633/webrev.01/
>
>>
>> ---
>> Previously, the calls to 'mark' and 'visited' were inlineable, but 
>> now every GC has to take a virtual call when marking the objects. My 
>> guess is that this code is slow anyway, and that it doesn't matter 
>> too much, but did you measure the effect of that change with, for 
>> example, G1?
>>
> I did rough measurement, timing 
> vmTestbase/nsk/jvmti/unit/heap/HeapWalkTests/TestDescription.java test.
>
> If you know any tests/benchmarks I should measure, please let me know.
>
> Thanks,
>
> -Zhengyu
>
>
>> Thanks,
>> StefanK
>>
>>> Test:
>>>    hotspot_gc
>>>    vmTestbase_nsk_jdi
>>>    vmTestbase_nsk_jvmti
>>>
>>> Thanks,
>>>
>>> -Zhengyu
>>>
>>>
>>
>