What influences young generation pause times?

Y. Srinivas Ramakrishna y.s.ramakrishna at oracle.com
Tue Apr 20 13:56:57 PDT 2010


On 04/20/10 13:30, Matt Khan wrote:
...
>  >> You could use -XX:+PrintSafepointStatistics etc. to figure these out.
> which other flags should I look at?

   product(bool, PrintSafepointStatistics, false,                            \
           "print statistics about safepoint synchronization")               \
                                                                             \
   product(intx, PrintSafepointStatisticsCount, 300,                         \
           "total number of safepoint statistics collected "                 \
           "before printing them out")                                       \


The o/p might go to stdout, rather than to the gc log file in
case you have the one redirected and not the other.

Once you know what those safepoints are for, you can use more specific
flags to see what's happening there (for example as Tony conjectured
perhaps biased locking; or global deoptimization due to class loading etc.)

-- ramki
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