Java Performance Tuning

Tuning After Deployment

Tuning does not necessarily end at the development stage. For many applications such as agent applications, services, servlets and servers, multiuser applications, enterprise systems, etc., there needs to be constant monitoring of the application performance after deployment to ensure that no degradation takes place. In this section, I discuss tuning the deployed application. This is mainly relevant to enterprise systems that are being administered. Shrink-wrapped or similar software is normally tuned the same way as before deployment, using standard profiling tools.

Monitoring the application is the primary tuning activity after deployment . The application should be built with hooks that enable tools to connect to it and gather statistics and response times. The application should be constantly monitored, and all performance logs retained. Monitoring should record as many parameters as possible throughout the system, though clearly you want to avoid monitoring so much that the performance of the running application is compromised by a significant amount. Of course, almost any act of measuring a system affects performance. But the advantage of having performance logs normally pays off enormously, and a few percent decrease in performance should be acceptable.

Individual records in the performance logs should include at least the following six categories:

• Time (including offset time from a reference server)

• User identifier

• Transaction identifier

• Application name, ...