Could you please share your expertise on this .Thanks!!
"re-starting the server." means what exactly? Stopping JBoss AS? How do you stop it? You waited until the java process disappeared from the list of processes before looking at your memory usage again?
Or you mean with restart:JBoss AS is running, take snapshot 1, restart (stop + start), take snapshot 2
When java process is terminated, all memory it consumed before will be released and given back to the OS. Otherwise your OS has a problem, neither JBoss nor your JDK can be the cause.
BTW OS, your OS seems to be AIX 6.x, right?
What's a "server crash"? A crash of the AIX machine?
I don't know mcuh about AIX and nothing about svmon. May be you misinterpret the numbers?
Unix systems use memory not occupied by processes for filesystem / buffer cache.
Thanks for the reply
Yes, While stopping the server. Java process is getting disappeared from the list of processes.
We are facing this issue after migrating the server from JBOSS 4.0.5.GA to JBOSS 7.
Here IBM JDK we are using is 64 bit.
Is it advisable to use 64 bit JDK for 8 GB RAM ?
64bit is the only option for >1.4G memory.
On windows, but on unix boxes limits are higher.
On Solaris 10 my WildFly is running with 32bit and "-Xms2G -Xmx2G -XX:PermSize=1g -XX:MaxPermSize=1g".
My experiance: if the needed memory is less than the limit of the 32bit version, you should use this as it gives you a slightly better performance and memore occupation is less compared to the 64 bit version.
Ah, apparently one can get ~4G on some OS:es with 32-bit