I have got the heap dumps by using jmap. I loaded it in eclipse MAT. java.lang.Thread is the top consumer. When I clicked on the immediate dominator, it shows a ArrayList with 17K objects(org.jboss.security.SecurityAssociation$SubjectContext) in it.
I took heap dumps at different time(2 hours interval).
java.lang.Thread @ 0xd09f05d0 pool-7-thread-1 Thread 112 | 12,198,024 | 7.64%
java.lang.Thread @ 0xd09e64c8 pool-7-thread-1 Thread 112 | 19,037,464 | 8.58%
Shallow Heap : 112 Retained Heap: 19,037,464 Percentage 8.58
Heap size is increasing.
The thread objects(0xd09f05d0 ,0xd09e64c8 ) are different, thread name is same(pool-7-thread-1). Is it still referring the same thread and its heap grows? Or one thread (0xd09f05d0 ) is completed its operation and the same thread with different object (0xd09e64c8 ) is used for different operation and it is holding different objects?