Jboss JVM option -Xmx -Xms

[sumesh_ps]

In our production server ,Server have 4GB RAM in that

1.We tried with -Xms512m -Xmx512m then what happed
one or two hours after restarting again system hangs up
and users not able to get the page.
2.Then we started testing with bigger value that will be most suitable.
Finally we have given -Xms:1576 , -Xmx:1576 ,-Xss128k.

3.Now what is happening is Server is running 3,4 days after that
free Heap size comes to 150-200m then Server hangs up.Then
after restart lot of heap free space and running fine.

what may be the possibilities for this issue?

Did any gone through situation like this ?

Friends suggest some solutions?

Thanks in advance

[yohanfer]

Hi,

Its probably best practice to have a heap size as small as possible. This will reduce the thread lockup caused by garbage collection. You can minimise the frequency of full collections by modifying the new generation size by setting the
-XX:NewSize and -XX:MaxNewSize settings also there is -XX:SurvivorRatio which you can play around with. Use -verbose:gc switch to see the GC performance.

See
http://java.sun.com/docs/hotspot/gc1.4.2/

for a detailed description....

Yohan Fernando