AFP

Default
Start of changeAFP(NOVOLATILE)End of change
Recommended
AFP(NOVOLATILE)
Reasoning

Start of changeWhen AFP(VOLATILE) is specified, values cannot be saved in registers FP8-FP15 during calls. They must instead be saved in memory and subsequently restored. The performance impact is most significant for small programs called many times.End of change

The use of AFP(NOVOLATILE) over AFP(VOLATILE) reduces the overhead of a program call by Start of change10%End of change at OPT(2). Note this was measured in an otherwise empty COBOL program to emphasize the performance cost of this option and would be less of an overall degradation in a more substantial called program.

Considerations
Specifying AFP(NOVOLATILE) requires a CICS® Transaction Server V4.1 or later.

related references
AFP (Enterprise COBOL for z/OS® Programming Guide)