Chapter 4. Java Specifics

In Chapter 2 we discussed the performance issues surrounding Java web applications, including key features of the J2EE specification. However, Java, unlike many other languages, also comes with its own runtime environment. Properly tuning the Java runtime environment often impacts the overall performance of your web site. This chapter presents some of the most common Java runtime performance issues that affect Java application servers. In particular, we discuss Java memory management, garbage collection, and memory leaks. We also cover key programming techniques, such as string management, multi-threading , and synchronization. These programming techniques often make the difference between a slow web site and a successful one.

In addition, we focus on Java runtime issues and parameters common across mid- tier platforms (NT, Windows 2000, AIX, Solaris, and HP/UX). However, your Java run-time provider may include other tuning parameters not mentioned in this chapter. (This is especially true for HP/UX.) Check with your JVM provider for additional tuning settings.