Request for review (M): 7178363 G1: Remove the serial code for PrintGCDetails and make it a special case of the parallel code

Bengt Rutisson bengt.rutisson at
Wed Jul 18 13:55:34 UTC 2012

Hi everyone,

I would like some reviews of this change:

This removes the special treatment for ParallelGCThreads=0 from the G1 
logging. I did keep the log output unchanged for that case. Basically it 
just has one indentation level less and skips some output. I am not sure 
this is really necessary since it is really a special case. I'm open to 
change that special treatment too and just have the same output as for 

The PrintGCDetails log output should be the same as before with three 
minor adjustments:

- The "Sum" is now not printed for the start and end values for GC 
workers. This sum does not really make sense to me.

- The "(ms)" unit was removed from output that aren't in milliseconds 
(termination attempts for example).

- The average value is now printed as a double for all types.

I tried to clean up the code a bit and introduced a separate class, 
Snippet WorkerDataArray, to keep track of the per thread logging. I also 
introduced getters and setters to avoid having to make G1CollectorPolicy 
and TraceGen0TimeData friend classes to G1GCPhaseTimes.


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