Enabling automated heap dump generation
Use this task to enable automated heap dump generation. This function is not supported when using a Sun Java virtual machine (JVM) which includes WebSphere Application Server running on HP-UX and Solaris operating systems. You need to research taking heap dumps on Sun JVMs or call IBM Support.
Before you begin
Although heap dumps are only generated in response to a detected memory leak, understand that generating heap dumps can have a severe performance impact on WAS for several minutes.
About this task
The automated heap dump generation support, which is available only on IBM Software Development Kit and analyzes memory leak problems on AIX, Linux, and Windows operating systems.
Manually generating heap dumps at appropriate times might be difficult. To help you analyze memory leak problems when memory leak detection occurs, some automated heap dump generation support is available. This functionality is available only for IBM Software Development Kit on AIX, Linux, and Windows operating systems.
Most memory leak analysis tools perform some forms of difference evaluation on two heap dumps. Upon detection of a suspicious memory situation, two heap dumps are automatically generated at appropriate times. The general idea is to take an initial heap dump as soon as problem detection occurs. Monitor the memory usage and take another heap dump when you determine that enough memory is leaked, so that we can compare the heap dumps to find the source of the leak.
To help you analyze memory leak problems when memory leak detection occurs, some automated heap dump generation support is available.
To enable automated heap dump generation support, perform the following steps in the administrative console:
Procedure
- Click Servers > Application servers in the administrative console navigation tree.
- Click servername >Runtime Performance Advisor Configuration.
- Click the Runtime tab.
- Select the Enable automatic heap dump collection check box.
- Click OK.
Results
The automated heap dump generation support is enabled.Important: To preserve disk space, the Runtime Performance Advisor does not take heap dumps if more than 10 heap dumps already exist in the WebSphere Application Server home directory. Depending on the size of the heap and the workload on the application server, taking a heap dump might be quite expensive and might temporarily affect system performance.
What to do next
We can monitor any notifications of memory leaks by checking the SystemOut.log file or Runtime Messages. For more information, see the Viewing the Runtime Performance Advisor recommendations topic. If a memory leak is detected and you want to find the heap dump, refer to the Locating and analyzing heap dumps topic.
See also
Generating heap dumps manually
Locating and analyzing heap dumps
Related information
Starting the lightweight memory leak detection