Optionally disabling logging

Because the information stored in the DFSMShsm log is duplicated elsewhere, such as SMF, PDA, and activity logs, it is recommended that you disable the log to improve performance, unless you need the DFSMShsm log for external reporting, such as from third-party products. If you choose not to use logging, use one of the following methods:

Specify a DD DUMMY statement in the startup procedure where HSMLOGX and HSMLOGY are allocated.
Do not specify any DD statements for log data sets.
Specify the HOLD LOG command in the DFSMShsm startup procedure.