JDK for Solaris Developer's Guide

Class Data Sharing

The class data sharing feature is aimed at reducing application startup time and footprint. The installation process loads a set of classes from the system jar file into a private, internal representation, then dumps that representation to a shared archive file. During subsequent JVM invocations, the shared archive is memory-mapped in, saving the cost of loading those classes and allowing much of the JVM's metadata for these classes to be shared among multiple JVM processes. For more information, refer to the documentation at http://java.sun.com/j2se/1.5.0/docs/guide/vm/class-data-sharing.html.