RFR(S): 8007701: Hotspot trace Allocation Events

Nils Eliasson nils.eliasson at oracle.com
Fri Mar 22 02:12:09 PDT 2013


Latest webrev after more feedback:

http://cr.openjdk.java.net/~neliasso/8007701/webrev.06/

//N


On 2013-03-20 16:24, Nils Eliasson wrote:
> Thanks for your review Erik,
>
> Updated the webrev with your suggestions
> - Moved alloction events to GCTrace
> - Renamed class event field to "class"
>
> http://cr.openjdk.java.net/~neliasso/8007701/webrev.04/
> http://bugs.sun.com/view_bug.do?bug_id=8007701
>
> //Nils Eliasson
>
>
> On 2013-03-14 21:42, Nils Eliasson wrote:
>> Hi all,
>>
>> I would like a review for this change that introduces two new tracing 
>> events.
>>
>> "AllocationInNewTLAB" is sent for the first object in a new TLAB and 
>> gives a reasonably cheap and reasonably fair object sampling.
>> "AllocationOutsideTLAB" is sent for each object that gets allocated 
>> outside the TLABs. (The object doesn't fit or would cause too much 
>> wasted free space if the tlab was discarded.)
>>
>> These events use the allocation slow path in CollectedHeap which is 
>> used by default in the template interpreter and the C2 compiler. It 
>> is also used for all TLAB refills in the C1-compiler if the flag 
>> -XX:-FastTLABRefill is supplied.
>>
>> http://cr.openjdk.java.net/~neliasso/8007701/webrev.03/
>> http://bugs.sun.com/view_bug.do?bug_id=8007701
>>
>> The event code for AllocationOutsideTLAB had to be put in 
>> CollectedHeap.cpp since tracing.hpp can't be included into 
>> CollectedHeap.inline.hpp.
>>
>> Thanks,
>> Nils Eliasson
>



More information about the hotspot-gc-dev mailing list