RFR(T) 8219244: NMT: Move safepoint related memory allocations from mtInternal to mtSafepoint

[coleen.phillimore at oracle.com]

On 2/19/19 4:07 PM, zgu at redhat.com wrote:
> Hi Coleen,
>
> On Tue, 2019-02-19 at 15:13 -0500, coleen.phillimore at oracle.com wrote:
>> This is such a small allocation, I think it makes more sense to add
>> it to mtThread.
> I get it if there is not mtSafepoint category, it is not worth to have
> one for a small allocation, but we already have it. Why is it better to
> add to mtThread?

Doesn't the current mtSafepoint category only report on mmap memory for 
the polling page?  This would add a very tiny allocation for the 
ThreadSafepointState (maybe too small to report?).  These allocations 
really belong to the thread.

Coleen

>
> Thanks,
>
> -Zhengyu
>
>
> Coleen
>> On 2/18/19 3:12 PM, zgu at redhat.com wrote:
>>> There is only one instance I can find.
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8219244
>>> Webrev: http://cr.openjdk.java.net/~zgu/JDK-8219244/webrev.00/
>>>
>>> Test:
>>>
>>>     hotspot_nmt on Linux x64 (fastdebug and release)
>>>     JDK-submit tests.
>>>
>>> Thanks,
>>>
>>> -Zhengyu
>>