Re: WO JVM Settings
Re: WO JVM Settings
- Subject: Re: WO JVM Settings
- From: Chuck Hill <email@hidden>
- Date: Mon, 20 Apr 2009 13:42:26 -0700
On Apr 20, 2009, at 10:26 AM, Dov Rosenberg wrote:
Does anyone have any input on the impact of various JVM settings?
Some of our professional services folks have offered up some of
their opinions but I can’t really judge if they are correct. Here
are the recommendations some of our folks have been implementing.
-server
On OS X that does nothing until Java 1.5 or 1.6.
-ms1400M -mx1400M
Those last two should be Xms and Xmx
-XX:+PrintGCDetails
That looks like a performance killer to me.
-XX:+UseCMSCompactAtFullCollection -XX:+UseConcMarkSweepGC -XX:
+UseParNewGC -XX:CMSFullGCsBeforeCompaction=0 -XX:
+CMSParallelRemarkEnabled -XX:+AggressiveHeap -XX:NewSize=100m -
XX:MaxNewSize=100m -XX:MaxPermSize=128m
Questions:
• For a long running WO app that utilizes EO’s which of the heaps
would be best to adjust?
• Are there any “rules of thumb” regarding sizing versus
performance and garbage collection for WO/EOF based apps?
I've never felt it necessary to tune any of these. Do they have a
reason for any of these?
I have not done enough investigation to know the affects of larger/
smaller NewSize, or the use of changing survivor ratio’s and messing
with how the objects move towards the tenured generations as I would
think the cached EO objects might be promoted to live there. Any
thoughts would be greatly appreciated.
The snapshots are more likely to get tenured. Tenure of the EO would
depend on how you use editing contexts.
Chuck
--
Chuck Hill Senior Consultant / VP Development
Come to WOWODC'09 in San Fran this June!
http://www.wocommunity.org/wowodc09/
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