RFR: JDK-8152952: Allow G1 phase logging to use individual number of threads (original) (raw)

Bengt Rutisson bengt.rutisson at oracle.com
Tue Mar 29 13:36:58 UTC 2016

Hi again,

I added some internal vm tests. Updated webrev:

http://cr.openjdk.java.net/~brutisso/8152952/webrev.01/

Diff compared to last version:

http://cr.openjdk.java.net/~brutisso/8152952/webrev.00-01.diff/

Thanks, Bengt

On 2016-03-29 14:03, Bengt Rutisson wrote:

Hi everyone, Could I have a couple of reviews for this change? http://cr.openjdk.java.net/~brutisso/8152952/webrev.00/ https://bugs.openjdk.java.net/browse/JDK-8152952 Currently if you run with UseDynamicNumberOfGCThreads you can potentially get a different number of worker threads each GC. There are improvements coming where we want to select a different number of worker threads for individual phases. The G1GCPhaseTimes and WorkerDataArray structures need to support this. The proposed patch sets all slots in the WorkerDataArray to an uninitialized value and then only print any values that have actually been set for that phase. The patch also extends the log message about the number for worker threads to also say how many it could potentially have used. And it also fixes a missing space in the level 3 and level 4 indentation. After applying this patch and running with -Xlog:gc*,phases*=trace you get output like: [0,581s][info][gc,task ] GC(0) GC Workers: using 2 out of 23 [0,588s][info][gc,phases] GC(0) Evacuate Collection Set: 5,0ms [0,588s][trace][gc,phases] GC(0) GC Worker Start (ms): Min: 580,9, Avg: 580,9, Max: 580,9, Diff: 0,0 [0,588s][trace][gc,phases,task] GC(0) 580,9 580,9 - - - - - - - - - - - - - - - - - - - - - [0,588s][debug][gc,phases ] GC(0) Ext Root Scanning (ms): Min: 1,7, Avg: 1,7, Max: 1,8, Diff: 0,0, Sum: 3,5 [0,589s][trace][gc,phases,task] GC(0) 1,8 1,7 - - - - - - - - - - - - - - - - - - - - - [0,589s][trace][gc,phases ] GC(0) Thread Roots (ms): Min: 0,0, Avg: 0,7, Max: 1,5, Diff: 1,5, Sum: 1,5 [0,589s][trace][gc,phases,task] GC(0) 0,0 1,5 - - - - - - - - - - - - - - - - - - - - - Thanks, Bengt

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