Terminating or disabling the JVM pool

CICS reduces the number of active JVMs automatically if the workload does not require them. If a JVM is inactive for 30 minutes, it is discarded.

You can terminate all the JVMs in the JVM pool by using a CEMT SET JVMPOOL PHASEOUT, PURGE or FORCEPURGE command (or the equivalent EXEC CICS command). When you use this command, all the JVMs in the pool, both worker JVMs using the shared class cache and standalone JVMs running independently of the shared class cache, are terminated. The shared class cache is also terminated once all the worker JVMs that were dependent on it have been terminated. On the CEMT SET JVMPOOL command:

You can also disable the JVM pool so that it cannot service new requests, by using a CEMT SET JVMPOOL DISABLED command (or the equivalent EXEC CICS command). When you disable the JVM pool, the JVMs in it are retained, but new Java programs cannot use them until you enable the JVM pool again. Java programs that are already using a JVM are allowed to finish running. To re-enable the JVM pool, use the CEMT SET JVMPOOL ENABLED command (or the equivalent EXEC CICS command).