G1:long remark pauses

Bengt Rutisson bengt.rutisson at oracle.com
Fri May 16 10:58:34 UTC 2014


Hi Thomas,

It looks like the application is using a lot of Reference objects. The 
time spent in remark is dominated by reference processing. See the 
attached graph generated from the log file you sent.

You can try to see if adding -XX:+ParallelRefProcEnabled improves the 
situation.

If the customer is interested in updating their application they might 
want to see if they can reduce the number of java.lang.ref.Reference 
objects they use.

Hths,
Bengt


On 2014-05-16 10:26, Thomas Viessmann wrote:
> Hi,
>
>
> I've been tuning a Java 7u51, Solaris 10, T4 system with 24G heap.
> My customer is not very happy with the remark pauses of  up to 2 seconds.
>  -XX:ParallelGCThreads=48 turned out to be the optimum. Here is the 
> log file
> which contains the java args at the top:
>
> http://aubing.de.oracle.com/gclog/gc_log_03052014.log
>
> Any idea to drive the remark stop times further down?
>
>
> Thanks and Regards
>
> Thomas

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