The SAS 9.3 ARM interface preserves the existing SAS
9.1 ARM interface as much as possible. The ARM interface enables applications,
tools, and facilities developed in SAS 9.1 ARM interface and ARM 2.0
to execute without change using ARM 4.0. But, adding the new performance
(PERF) macros reduces performance overhead. The following sections
document how to add the SAS 9.3 ARM interface to existing SAS applications: