[8u60] Request for backport approval: 8055416 Several vm/gc/heap/summary "After GC" events emitted for the same GC ID

[Michail Chernov]

Dear colleagues,

I'd like to get approval to backport changes from JDK9 to 8u.

Webrev: http://cr.openjdk.java.net/~eistepan/~mchernov/8055416/webrev.00/


Original issue was fixed and approved at August 2014. Here is the mail 
thread: 
http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2014-August/010549.html
JDK9 webrev: http://cr.openjdk.java.net/~stefank/8055416/webrev.00/

Original bug is https://bugs.openjdk.java.net/browse/JDK-8055416
"

For client VM and G1 GC several vm/gc/heap/summary events with property
when='After GC' could be emitted for the same GC ID.
At the same time there will be only one 'Before GC' vm/gc/heap/summary
event for the same GC ID."



Testing: JDK with changes was built locally. Closed JFR test has passed.

Thanks,
Michail