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.