ZCOMPRESS: Specifying when compression with zEDC should be done

Explanation: ZCOMPRESS is an optional parameter set that you use to specify the type of compression used during migration or backup for all data sets.

The subparameters of the ZCOMPRESS parameter follow this discussion in alphabetical order. The following are optional subparameters:

ALL | NONE
DASDBACKUP (YES | NO)
DASDMIGRATE (YES | NO)
TAPEBACKUP (YES | NO)
TAPEMIGRATE (YES | NO)

SMS relationship:

Parameter differs in meaning when applied to SMS-managed or non-SMS-managed DASD volumes or data sets. This ZCOMPRESS parameter is used only for SMS data sets that are not compressed on L0; for non-SMS data sets, it is always in effect, as you cannot have a non-SMS data set compressed on L0.

SETSYS default: If you do not specify the ZCOMPRESS parameter, the SETSYS default is no compression with zEDC.

DFSMShsm default: If you do not specify a subparameter with this parameter on any SETSYS command, the DFSMShsm default is no compression with zEDC.