On Wed, Feb 16, 2011 at 1:34 PM, Duncan <[email protected]> wrote: > java.args=-server -Xms4096m -Xmx8192m -Dsun.io.useCanonCaches=false
One thing I would be cautious about here: a heap that large can be susceptible to "stop the world" GC sweeps and if the heap ever grows near the 8GB max, those sweeps will take a significant amount of time. What you'll see is generally really, really good response times and then every now and then a complete freeze of your app for all users for 10-30 seconds, then back to really, really good response times. In general, for long running processes, I'd try to keep the heap between 2GB and 3GB and instead run multiple instances and distribute load that way instead. Also, the PermGen area is mostly for .class files so it needs to be large enough to hold "every" class your system is going to need but once it hits that, it shouldn't grow (unless you're running code that creates new class loaders and loads classes repeatedly, e.g., JavaLoader when it's not cached in server scope etc). I've never needed a PermGen size as big a 1GB but you might have many tens of thousands of .class files (either lots of files or lots of methods in CFCs). However, if your settings are working for now, that's good. JVM tuning tends to be an ongoing thing - and somewhat of a black art :( -- Sean A Corfield -- (904) 302-SEAN Railo Technologies, Inc. -- http://getrailo.com/ An Architect's View -- http://corfield.org/ "If you're not annoying somebody, you're not really alive." -- Margaret Atwood ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:342351 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
