Non-heap memory spikes

[itaomonitor]

http://java-monitor.com/postedimages/761d357b-48fa-4f76-b9e5-25481e4a07d6.png

Hello

Can anyone help in pointing me to the best places to look for the probable causes for why the NonHeap Memory usage is so high and why there would these spikes that goes close to the maximum?

Also what is the setting that makes the maximum 400mb, I don't believe I've set this in my startup scripts.

Thanks

[kjkoster]

Dear itaomonitor,

Regarding the 400MB: The setting you made is the combined maximum of a number of pools. It also influences the sizes of other pools. It is not an exact science. :) What are your start-up options?

Non-heap can be a lot of things. Generated code springs to mind, or large volumes of interned strings. Can you tell me a bit about the application? Does it auto-generate JSP files for example? What does it do?

Kees Jan

[itaomonitor]

set JAVA_OPTS=-server -Xmx1024M -Xms1024M -XX:+UseConcMarkSweepGC -XX:+UseCMSCompactAtFullCollection

the application uses Jasperreports a lot to print, but can't think of anything that would generate code, and the same application is deployed on another server (with even more workload) and that is not exhibiting the same readings

[kjkoster]

Dear itaomonitor,

I am curious which one of the options you expect to set the non-heap size? I always use -XX:MaxPermSize=...M to set the non-heap size.

What is different between the systems you describe? They have the same command line options?

You could take a memory analysis tool to the system and see what is in the non-heap pools. Not sure which tool is best for that nowadays.

Kees Jan