Use this topic to understand the benefits of tuning for optimal performance. Learn about
the tunable parameters of the major WebSphere® Application Server components
and how these parameters affect performance.
Before you begin
WebSphere Application Server provides tunable settings for its major
components so that you can adjust the runtime environment to match the characteristics of your
application. Applications can run successfully without changing the default values for these tuning
parameters. Other applications might need changes, for example, a larger heap size, to achieve
optimal performance.
Performance tuning can yield significant gains in performance even if an application is not
optimized for performance. However, correcting shortcomings of an application typically results in
higher performance gains than are possible with just altering tuning parameters. Many factors
contribute to a high performing application.
Procedure
- Run the applyPerfTuningTemplate.py script as the starting point for
improving the performance of a specific application server.
This python-based tuning
script, along with one of its template files, applies the recommended performance tuning settings
for a typical development, production, or environment that is ready for immediate use. The
applyPerfTuningTemplate.py script, and its associated templates and properties
files, are located in the WAS_HOME/bin directory.
- Use the performance advisors, the suggested procedures or parameters in the tuning
parameter hot list, and the information on troubleshooting performance problems to optimize your WebSphere Application Server instances to their fullest extent.
- Performance advisors
- The performance advisors use the Performance Monitoring Infrastructure (PMI) data to suggest
configuration changes to Object Request Broker (ORB) service thread pools, web container thread
pools, connection pool size, persisted session size and time, prepared statement cache size, and
session cache size. The Runtime Performance Advisor runs in the application server process, while
the other advisor runs in the Tivoli Performance Viewer. For more information, see the documentation
about using the Performance and Diagnostic Advisor and use the performance advisor in Tivoli
Performance Viewer.
- Tuning parameter hot list
- Review the documentation about the tuning parameter hot list. These parameters have an important
impact on performance. Because these parameters are application-dependent, the parameter settings
for specific applications and environments can vary.
- Troubleshooting performance
- To save you time detecting problems and help you troubleshoot performance problems, see the
documentation about troubleshooting performance.