Generating heap dumps manually
Use this task to generate heap dumps manually. This function is not supported on when using a Sun Java™ virtual machine (JVM) which includes WebSphere® Application Server running on HP-UX and Solaris operating systems.
Before you begin
Although heap dumps are generated only in response to a detected memory leak, you must understand that generating heap dumps can have a severe performance impact on WebSphere Application Server for several minutes. When generating multiple heap dumps manually for memory leak analysis, make sure that significant objects are leaked in between the two heap dumps. This approach enables problem determination tools to identify the source of the memory leak.
About this task
You might want to manually generate heap dumps for the analysis of memory leaks. You might also want to designate certain times to take heap dumps because of the overhead involved. On JVM in WebSphere Application Server, you can manually produce heap dumps by using the generateHeapDump operation on WebSphere Application Server managed beans (MBeans) that are special Java beans.
On a Java virtual machines (JVM) in WebSphere Application Server, you cannot enable automated heap dump generation.
The WebSphere Application Server wsadmin tool provides the ability to run scripts. You can use the wsadmin tool to manage a WebSphere Application Server installation, as well as configuration, application deployment, and server runtime operations. WebSphere Application Server supports the Jacl and Jython scripting languages only. To learn more about the wsadmin tool, see the starting the wsadmin scripting client information.
Procedure
What to do next
After running the wsadmin command, the file name of the heap dump is returned. For more information on finding heap dumps, refer to the Locating and analyzing heap dumps topic. When you have a couple of heap dumps, use a number of memory leak problem determination tools to analyze your problem. Memory Dump Diagnostic for Java™ is an offline tool for diagnosing root causes behind memory leaks in the Java heap. See the diagnosing out-of-memory errors and Java heap memory leaks information.