Am 17.06.2016 um 09:06 schrieb Ere Maijala:
> 16.6.2016, 1.41, Shawn Heisey kirjoitti:
>> If you want to continue avoiding G1, you should definitely be using
>> CMS. My recommendation right now would be to try the G1 settings on my
>> wiki page under the heading "Current experiments" or the CMS settings
>> just below that.
>
> For what it's worth, we're currently running Shawn's G1 settings slightly
> modified for our workload on Java 1.8.0_91 25.91-b14:
>
> GC_TUNE=" \
> -XX:+UseG1GC \
> -XX:+ParallelRefProcEnabled \
> -XX:G1HeapRegionSize=16m \
> -XX:MaxGCPauseMillis=200 \
> -XX:+UnlockExperimentalVMOptions \
> -XX:G1NewSizePercent=3 \
> -XX:ParallelGCThreads=12 \
> -XX:+UseLargePages \
> -XX:+AggressiveOpts \
> "
-XX:G1NewSizePercent
<Garbage First Garbage Collector Tuning (oracle.com)>
... Sets the percentage of the heap to use as the minimum for the young
generation size.
The default value is 5 percent of your Java heap. ...
So you are reducing the young heap generation size to get a smoother running
system.
This is strange, like reducing the bottle below the bottleneck.
Just my 2 cents.
Regards
Bernd
>
> It seems that our highly varying loads during day vs. night caused some
> issues leading to long pauses until I added the G1NewSizePercent (which
> needs +UnlockExperimentalVMOptions). Things are running smoothly and there
> are reports that the warnings regarding G1 with Lucene tests don't
> happen anymore with the newer Java versions, but it's of course up to you if
> you're willing to take the chance.
>
> Regards,
> Ere
