When running the JVM at SDK 1.4 or higher, there are options provided to allow you to control Java™ code execution on zAAPs. The default value will cause Java code to be dispatched to zAAPs. The option is specified with other Java startup options. You can use these JVM options to compare execution results of Java code on standard CPs and zAAPs.
-Xifa:on: This is the default. The -Xifa:on option indicates to the JVM to call the switch service for zAAPs. If there are no zAAPs available, the JVM will silently disable switching. Once the JVM calls the switch service successfully, it will continue calling the switch service, even if the last zAAP goes offline.
-Xifa:force: The -Xifa:force option indicates to the JVM to always call the switching service for zAAPs, even when there are no zAAPs online. As mentioned previously, this option is useful when gathering information for capacity planning.
-Xifa:off: The -Xifa:off option indicates to the JVM to bypass all switching to zAAPs. This causes all Java work to be executed on standard CPs.
Refer to Java Diagnostics Guide for more information on setting the -Xifa startup option in the JVM.