Each active log is held on a single data space. After an active log is opened, it remains open as long as the PowerExchange Logger for z/OS is active. The more active logs are allocated, the more data spaces are opened while the PowerExchange Logger is active.

If PowerExchange must be available continuously for near-real-time replication, use a small number of active log data sets.

If you are not concerned about controlling the amount of archiving, use a larger number of active data sets. Archiving will occur more frequently but take less time.