With z/OS V2R1, a new ZCOMPRESS keyword has been added to the DUMP command to specify that DFSMSdss writes the dumped data in compressed format to the output medium using zEDC Services. This decreases the space occupied by the dumped data.
For more information, refer to the DUMP command in z/OS DFSMSdss Storage Administration.
For more information on zEDC, see Using the zEnterprise Data Compression (zEDC) enhancements.