
50 Introduction to the New Mainframe: z/VSE Basics
In addition to these characterizations of processors, some mainframes have
models or versions that are configured to operate slower than the potential speed
of their CPs. This is widely known as
kneecapping, although IBM prefers the term
capacity setting, or something similar. It is done by using microcode to insert null
cycles into the processor instruction stream. The purpose, again, is to control
software costs by having the minimum mainframe model or version that meets
the application requirements. IFLs, SAPs, zAAPs, and ICFs always function at
the full speed of the processor since these ...