The level of reusability for a JVM is specified by the REUSE option in the JVM profile.
JVMs that use the shared class cache, known as worker JVMs, inherit their level of reusability from the REUSE option that you specify in the JVM profile for the master JVM. If you include the REUSE option in the profile for a worker JVM, the option is ignored. Defining the shared class cache explains what to consider when choosing a level of reusability for the master and worker JVMs.
For standalone JVMs that do not use the shared class cache, the REUSE option in the JVM profile determines the level of reusability. REUSE=RESET, which produces a resettable JVM, is the default if no REUSE option is specified.
The older option Xresettable is also accepted for migration purposes. If this option is present in the JVM profile and specified as Xresettable=YES, the JVM is resettable. If Xresettable=NO is specified, the JVM is single-use. The Xresettable option cannot be used to specify a continuous JVM. If the Xresettable option and the REUSE option are both present in the JVM profile and they conflict, the REUSE option overrides the Xresettable option, and an information message is issued. It is advisable to remove the Xresettable option if both the options are present.
When you are specifying JVM profiles for continuous JVMs, bear in mind that if more than one application uses the same JVM profile that creates a continuous JVM, the applications could see each other's persistent state. If you need to ensure that an application that uses a continuous JVM does not have any contact with the persistent state from another application, you should create separate JVM profiles for the applications to use. (The JVM profiles can be identical in content, provided that they have different eight-character names.)