AFP
- Default
AFP(NOVOLATILE)
- Recommended
- AFP(NOVOLATILE)
- Reasoning
-
When 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.
The use of AFP(NOVOLATILE) over AFP(VOLATILE) reduces the overhead of a program call by
10%
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.