On 03/10/2016 07:59 PM, Yasumasa Suenaga wrote:
Hi all,
This review request continues from:
http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-March/016774.html
http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-March/016896.html
I wonder that STW phases (Remark and Cleanup) at G1 are not counted in jstat
FGC column.
For example, Initial Mark and Remark at CMS are counted as FGC.
We discussed on hotspot-gc-dev for this issue, and I proposed to add new
PerfCounter
for CGC STW phases.
I uploaded webrev. Could you review it?
hotspot:
http://cr.openjdk.java.net/~ysuenaga/JDK-8151674/webrev.00/hotspot/
jdk: http://cr.openjdk.java.net/~ysuenaga/JDK-8151674/webrev.00/jdk/
For compatibility, this patch works the same as the current by default.
If you set -XX:+EnableConcGCPerfCounter, CGC counter will work fine.
(I want to set +EnableConcGCPerfCounter by default)
I would prefer not to have the flag (EnableConcGCPerfCounte)
and just make the change for CMS. This is a change for a major
release and I think we can accept the incompatibility.
http://cr.openjdk.java.net/~ysuenaga/JDK-8151674/webrev.00/hotspot/src/share/vm/gc/g1/g1MonitoringSupport.cpp.udiff.html
+ // name "collector.2". In a generational collector this would be the
+ // STW phases in concurrent collection.
+ _conc_collection_counters =
+ new CollectorCounters("G1 stop-the-world phases", 2);
Is there a hard connection between these phases and a generational
collector (i.e., should the "In a generational collector this would be the"
be dropped in the comment)?
A comment such as
// name "collector.2". STW phases as part of a concurrent collection.
A set of JDK changes had been previously been reviewed (not by me). Are
these
the same?
http://cr.openjdk.java.net/~ysuenaga/JDK-8151674/webrev.00/jdk/
Jon
I cannot access JPRT.
So I need a sponsor.
Thanks,
Yasumasa
