MVS Jan 2005.p65 - CBT Tape

-Xifa:force – this is designed to force Java to continue
attempting to use zAAP, even if none are available. It
would typically be specified for the purpose of collecting
RMF/SMF data to assess potential zAAP and applicable
only to z/OS 1.6
Note that the command line options that start with –X refer to
non-standard Java interpreter options and are anticipated to
be unique to IBM.
zAAP-ELIGIBLE WORK ON STANDARD CP
z/OS 1.6 provides two new options, IFACrossOver and
IFAHonorPriority, that can be defined in the IEAOPTxx member
of SYS1.PARMLIB. They control how zAAP-eligible work is
switched between standard processors and zAAPs.
The following gives a summarized view of the CrossOver
parameter.
IFACrossOver = Yes (default) allows crossover, permitting
Java work to compete for standard CP resources in addition
to executing on zAAPs. It is used when the preference is to
fully utilize the cheaper zAAP resource. Its disadvantage is
that it prevents the execution of Java work in standard CP
even if it is available and zAAPs are fully utilized.
IFACrossOver = No means the standard processor may not
run any zAAP-eligible work unless there is no zAAP operating
in the LPAR. It is used when the flexibility of using the standard
CP for Java is required. Its disadvantage is that tracking work
is complex and the cost of Java processing is higher.
When crossover is permitted, the amount of Java crossing
over onto the standard CPs can be controlled by the
HonorPriority setting.
With IFAHonorPriority = Yes (default), WLM will manage the
priority of zAAP-eligible work for standard processors. It can
be used when the Java work has to be dispatched ahead of
any lower priority non-Java work.
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