"Sam" <samit.katiyar@gmail.com> said:

...

Well, you have three choices:
- you've not allocated enough memory to your server
 (JVM startup parameters)
- your code is leaking memory (or, WebLogic server is leaking
 memory, but your code is more probable of the two)
- your code (or, again, WebLogic server code) is causing
 memory fragmentation; that is, there is free JVM heap
 available, but not in large enough contiguous chunks

The first two: look at the memory utilization of your system
(WebLogic console provides graphing tools for this); if it's
steady, linear growth of used memory, and you get OutOfMemory
when the curve hits the top, then there either is not enough
memory or the application is leaking memory. Make an educated
guess whether your application should consume the amount of
memory you've allocated for it, and if it could, increase the
memory allocation. Do this until your memory allocation is
so large that you're certain that you've exceeded the run size
of your application. If you still encounter the OutOfMemory
errors, your code is leaking memory (i.e. not properly releasing
references to created objects), and should be fixed.

The third: looking at the memory usage graph, you get OutOfMemory
error when there seemingly is still memory available. Allocating
more memory may help, also changing VM memory-related parameters
may help.