RFR: JDK-8151674: STW phases at Concurrent GC should count in PerfCounter (original) (raw)

Yasumasa Suenaga yasuenag at gmail.com
Fri Mar 18 14:14:44 UTC 2016

Hi,

I added a comment to JBS about G1 initial mark. I will upload new webrev after discussing for it.

We discussed about it on JBS, and we decided not to count initial mark on G1 to CGC counter. [1]

I uploaded new webrev. Could you review it?

hotspot: http://cr.openjdk.java.net/~ysuenaga/JDK-8151674/webrev.01/hotspot/ jdk: http://cr.openjdk.java.net/~ysuenaga/JDK-8151674/webrev.01/jdk/

jdk part is the same with the patch which is reviewed by Staffan Larsen. [2]

Thanks,

Yasumasa

[1] https://bugs.openjdk.java.net/browse/JDK-8151674?focusedCommentId=13914167&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13914167 [2] http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-March/016911.html

On 2016/03/17 8:23, Yasumasa Suenaga wrote:

Hi Jon,

2016/03/17 3:25 "Jon Masamitsu" <jon.masamitsu at oracle.com <mailto:jon.masamitsu at oracle.com>>: > > > > 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. Okay, I will remove this flag. I added a comment to JBS about G1 initial mark. I will upload new webrev after discussing for it. > 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. > + conccollectioncounters = > + 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. Thanks, I will fix. > 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/ Yes, same patch. Yasumasa > Jon > > > >> >> >> I cannot access JPRT. >> So I need a sponsor. >> >> >> Thanks, >> >> Yasumasa > >

More information about the hotspot-gc-dev mailing list