For short-running jobs, improving Java™ start up time is important. This is especially true when running numerous small Java batch jobs, as the Java start up elapsed time and CPU time may affect performance. Using the following Java options can make it possible to reduce the Java startup times for applications that frequently start a new JVM :

• -Xquickstart Java option
  Note: Quickstart may improve startup time for short running jobs, but it may degrade performance of long running applications.
• Shared classes and AOT Java options

For more details about this topic as well as the latest considerations for using Java, performance information, hints and tips, and information about developing and running applications see:

http://www.ibm.com/systems/z/os/zos/tools/java