thread dump & core dump both are same or is their any difference between them,
if difference is their how to generate core dump and what is use of core dump? 

Hi Saravana

    Thread dump (javacore*.txt): This type has all threads that are running in the process. This is a human readable dump designed to summarize the state of the process in high level terms.
    
    IBM Portable Heap Dump (*.PHD): This IBM format contains the type and size of each Java object in the process, and the relationships among the objects.
    HPROF binary dump: The HPROF binary format contains all the data present in the IBM PHD format as well as the primitive data held inside the Java objects, and the thread details.
    
    IBM system dumps (core*.dmp): This is a complete dump of all the information in a process. When the IBM Java runtime is being used, the native operating-system dump file — a core file on AIX® or Linux, a minidump on Windows®, or a SVC dump on z/OS®

    Check my article about dumps
    http://www.websphereusergroup.org/go/article/view/websphere_application_server/260173/websphere_application_server_v8:_demystifying_the_dumps

regards

Thank you very much gabriel for your quick response ,i had gone through your article it's very nice, can you tell me the command to generate coredump?

saravana,

  Depends on your WAS version.

  MustGather: Generating Javacores and Userdumps Manually For Performance, Hang or High CPU Issues on Windows
  www-01.ibm.com/support/docview.wss?uid=s...

  look wsadmin script section.

regards