Re: Artems: ParallelGC vs CMS

2017-02-09 Thread Tim Bain
Did Old Gen continually increase *after* performing full GCs? That is, was the Old Gen usage after full GC #N always greater than the Old Gen usage after full GC #N+1? If not, you were concerned about something that doesn't matter. It's OK for Old Gen to grow; that's why we have a garbage collecto

Re: Artems: ParallelGC vs CMS

2017-02-08 Thread abhijith
Yes, we tested with G1 settings in load test environment. Old gen was still increasing with it albeit a bit slower than parallel GC, so we never moved ahead with it. -- View this message in context: http://activemq.2283324.n4.nabble.com/Artems-ParallelGC-vs-CMS-tp4721722p4721737.html Sent from

RE: Artems: ParallelGC vs CMS

2017-02-08 Thread Tim Bain
I second the suggestion about G1GC; if you would consider running CMS (which is a hand grenade, and should be used only once you understand the risk of Old Gen fragmentation and how it could result in an OOM even though there is lots of RAM available), you should be considering G1 as well (and sinc

RE: Artems: ParallelGC vs CMS

2017-02-08 Thread nigro_franz
I didn't know the "incremental mode" is being deprecated, great! -- View this message in context: http://activemq.2283324.n4.nabble.com/Artems-ParallelGC-vs-CMS-tp4721722p4721748.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.

RE: Artems: ParallelGC vs CMS

2017-02-08 Thread Richard Wagg
CMS should not be used in incremental mode for any modern hardware - see https://docs.oracle.com/javase/8/docs/technotes/guides/vm/gctuning/cms.html. Try the below, and take a look at what the GC log output shows? -Xms8G -Xmx8G -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSClassUnloadingEn

Re: Artems: ParallelGC vs CMS

2017-02-08 Thread nigro_franz
Just a few ideas... CMS is not a compacting collector, which can result in old generation fragmentation: if there will be any memory leaks in the connection's resources that makes the old generation filled with fragmented garbage, a FullGC (with no results due to the leak!) is triggered to compact

Re: Artems: ParallelGC vs CMS

2017-02-07 Thread Francesco Nigro
Hi! Just as a chrioisty, do you have tried G1 too? Il mar 7 feb 2017, 22:07 abhijith ha scritto: > Hi, > > Has there any test done for Artemis using CMS GC? > > Context: We were using default parallel GC with 6G RAM and were facing an > issue where old gen was filling up without full GC being