Enable automated heap dump generation
Overview
Heap dumps are generated in response to a detected memory leak. Generating heap dumps can have a severe performance impact on WAS for several minutes.
Automated heap dump generation is not supported when using a Sun JVM which includes WAS running on HP-UX and Solaris operating systems. We need to research taking heap dumps on Sun JVMs or call IBM Support.
Automated heap dump generation support, available on the IBM SDK, works on...
- AIX
- Linux
- Windows
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 you 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
Servers | Application servers | server | Performance and Diagnostic Advisor Configuration | Runtime tab | Enable automatic heap dump collection check box | OK
Results
The automated heap dump generation support is enabled.
To preserve disk space, the Performance and Diagnostic Advisor does not take heap dumps if more than 10 heap dumps already exist in the WAS home directory. Depending on the size of the heap and the workload on the appserver, taking a heap dump might be quite expensive and might temporarily affect system performance.
What to do next
You can monitor any notifications of memory leaks by checking the SystemOut.log file or Runtime Messages.If a memory leak is detected and you want to find the heap dump, refer to the Locating and analyzing heap dumps topic.
Generate heap dumps manually
Locate and analyze heap dumps
Related information
Start the lightweight memory leak detection