RFR(S): 8139673: NMT stack traces in output should show mt component

[Coleen Phillimore]

I wonder if you can lookup the memory type with the stack trace in the 
MallocSiteTable before creating a new one.  Have the hash function 
include the mtType.
Coleen


On 1/11/17 7:55 AM, Zhengyu Gu wrote:
> Hi Chris,
>
> I am not convinced that 4 frames is sufficient, and skipping more 
> frames can result ambiguous path.
>
> Or you may want to consider "OR" the memory types in the allocation 
> site record, so it at least can report all possible memory types at 
> this particular site.
>
> Thanks,
>
> -Zhengyu
>
>
> On 01/10/2017 11:20 PM, Chris Plummer wrote:
>> Hi Zhengyu,
>>
>> I think in theory you are right, but in practice probably each call 
>> site is always using the same allocation type, as long as we are 
>> going at least 4 frames back. If 4 frames is not enough, then either 
>> we should be going back more frames, or we are not skipping enough 
>> frames in some cases.
>>
>> thanks,
>>
>> Chris
>>
>> On 1/10/17 10:02 AM, Zhengyu Gu wrote:
>>> I don't think that this enhancement makes sense. NMT only records 
>>> last part of call path that leads memory allocation, which can be 
>>> shared by many allocation paths and from
>>> different sub systems.
>>>
>>> You are tagging the call site with the type of the first call, I 
>>> think it can be misleading and incorrect.
>>>
>>> Thanks,
>>>
>>> -Zhengyu
>>>
>>>
>>>
>>>
>>>
>>> On 01/10/2017 11:16 AM, Max Ockner wrote:
>>>> Hello,
>>>> Please review this small enhancement to NMT detail report. I have 
>>>> added the memory type to the output for each NMT stacktrace.
>>>>
>>>> Bug:  https://bugs.openjdk.java.net/browse/JDK-8139673
>>>> Webrev: http://cr.openjdk.java.net/~mockner/8139673/
>>>>
>>>> The old stacktrace output looks like this:
>>>>
>>>> [0x00007f17135fdd93] OSThread::pd_initialize()+0x63
>>>> [0x00007f17135fdc7f] OSThread::OSThread(int (*)(void*), void*)+0x2f
>>>> [0x00007f171360e020] os::create_thread(Thread*, os::ThreadType, 
>>>> unsigned long)+0x80
>>>> [0x00007f17139d1d3d] AbstractWorkGang::add_workers(unsigned int, 
>>>> bool)+0x18d
>>>>                              (malloc=2KB #10)
>>>>
>>>> The new stacktrace output looks like this:
>>>>
>>>> [0x00007f17135fdd93] OSThread::pd_initialize()+0x63
>>>> [0x00007f17135fdc7f] OSThread::OSThread(int (*)(void*), void*)+0x2f
>>>> [0x00007f171360e020] os::create_thread(Thread*, os::ThreadType, 
>>>> unsigned long)+0x80
>>>> [0x00007f17139d1d3d] AbstractWorkGang::add_workers(unsigned int, 
>>>> bool)+0x18d
>>>>                              (malloc=2KB type=Internal #10)
>>>>
>>>> Tested with jtreg NMT tests.
>>>>
>>>> Thanks,
>>>> Max
>>>
>>
>