RFR(S): 8007701: Hotspot trace Allocation Events

Nils Eliasson nils.eliasson at oracle.com
Wed Mar 20 08:24:47 PDT 2013


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



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