Java Enterprise Best Practices

Tuning Techniques

Java Enterprise performance-tuning techniques include J2SE tuning techniques, as well as a variety of others. Here is a summary of the J2SE best practice techniques:

• Improve CPU limitations with faster code, better algorithms, and fewer short-lived objects.

• Improve memory limitations by using fewer objects or smaller long-lived objects.

• Improve I/O limitations by reducing the number of I/O operations with targeted redesigns, or by speeding up I/O by reducing the amount of data requiring I/O, or perhaps by multithreading the I/O. Buffer I/O where possible (usually almost everywhere).

• Switch to an optimizing compiler.

• Use a JIT-enabled JVM.

• Test other JVMs to find a faster one.

• Turn off any JVM options that slow down the application (e.g., -Xrunhprof and -verbose ).

• Tune the heap.

• If a bottleneck consists of a slow method, make it faster.

• If a bottleneck consists of many calls to a fast method, reduce the number of times that method is called.

• Tune object-creation and garbage-collection bottlenecks by reusing objects and reducing the number of objects used.

• Target loops. Minimize the time executed in the loop by moving any code you can outside the loop, avoiding repeated operations and inlining method calls.

• Target strings. Only internationalized text needs to use String objects. All other string use can probably be optimized with your own character handling.

• Try to use primitive datatypes directly. Avoid wrapping them.

• Use or build the fastest collection possible. Traverse ...