The following options influence performance when using the index
of a key-sequenced data set or variable-length RRDS. Each option improves
performance, but some require that you provide additional virtual
storage or auxiliary storage space. The options are:
- Specifying enough virtual storage to contain all index-set records
(if you are using shared resources).
- Ensuring that the index control interval is large enough to contain
the key of each control interval in the control area.
- Placing the index and the data set on separate volumes.