Request for Review - 8152208: Summary for phase times are incorrect with and without UseDynamicNumberOfGCThreads (original) (raw)

Bengt Rutisson bengt.rutisson at oracle.com
Mon Mar 21 09:13:52 UTC 2016

Hi Jon,

On 2016-03-21 03:43, Jon Masamitsu wrote:

The averages reported for phase times (for example "Ext Root Scanning") were incorrect. Not all the per thread values were included in the sum and the average value was incorrect (this with build 9-ea+1100)

[0.366s][debug][gc,phases ] GC(2) Ext Root Scanning (ms): Min: 0.3, Avg: 0.2, Max: 0.4, Diff: 0.0, Sum: 0.3 [0.366s][trace][gc,phases,task ] GC(2) 0.4 0.3 With the fix all values are included in the sum and the average is correct. [2.830s][debug][gc,phases ] GC(0) Ext Root Scanning (ms): Min: 5.7, Avg: 7.3, Max: 8.9, Diff: 3.1, Sum: 14.6 [2.830s][trace][gc,phases,task ] GC(0) 8.9 5.7 https://bugs.openjdk.java.net/browse/JDK-8152208 http://cr.openjdk.java.net/~jmasa/8152208/webrev.00/

Nice catch! Your change looks good.

The method WorkerDataArray::sum(uint active_threads) just above the average() method has the same issue. Can you fix that too?

Thanks, Bengt

Thanks. Jon

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