This topic describes the benefits of tuning for optimal performance, highlights the tunable parameters of the major WebSphere Application Server components, and provides insight about how these parameters affect performance.
WebSphere Application Server provides tunable settings for its major components to enable you to make adjustments to better match the runtime environment to the characteristics of your application. Many applications can run successfully without any changes to 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 larger performance gains than are possible with just altering tuning parameters. Many factors contribute to a high performing application.
About this task
To optimize your WebSphere Application Servers to their fullest extent, use the performance advisors, the suggested procedures or parameters in the tuning parameter hot list, and the troubleshooting performance checklist.
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 (TPV). For more information, see the articles, Using the Runtime Performance Advisor
and Using the performance advisor in Tivoli Performance Viewer
.
Tuning parameter hot list
Review 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.
The tuning guide focuses on server tuning. If you want to tune your applications, see the Performance: Resources for learning article for more information about application tuning.
For your convenience, procedures for tuning parameters in other products, such as DB2, Web servers and operating systems are included. Because these products might change, consider these descriptions as suggestions.
Each WebSphere Application Server process has several parameters that influence application performance. You can use the WebSphere Application Server administrative console to configure and tune applications, Web containers, EJB containers, application servers and nodes in the administrative domain.
Each parameter description: explains the parameter; provides reasons to adjust the parameter; discusses how to view or set the parameter; as well as indicates default and recommended values.
The Troubleshooting performance topic can save you time detecting problems and help you troubleshoot performance problems.
OS/400 heap monitor
New for V6.0.2, the OS/400 heap monitor helps to monitor the Java Virtual Machine (JVM) heap size of a WebSphere Application Server profile in comparison to pool size. See OS/400 heap monitor for more information. Additional references:
Related reference
DB2 Universal Database performance tips
Secure Sockets Layer performance tips
EJB method Invocation Queuing
Java memory tuning tips
Example: Choosing a topology for better performance
Performance: Resources for learning
HTTP transport custom properties
Searchable topic ID: tprf_tuneprf