Request for Review - 8152208: Summary for phase times are incorrect with and without UseDynamicNumberOfGCThreads
Jon Masamitsu
jon.masamitsu at oracle.com
Mon Mar 21 03:06:42 UTC 2016
Review is small.
Tested with and without UseDynamicNumberOfGCThreads with
the tested added for this fix.
On 3/20/2016 7:43 PM, 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/
>
> Thanks.
>
> Jon
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