![Start of change](./delta.gif)
Creating Compressed-Format PDSEs
To create compressed-format PDSEs, your security administrator must enable it by defining the discrete FACILITY class STGADMIN.SMS.ALLOW.PDSE.COMPACT. In addition, your storage administrator must specify COMPACTION ZP or COMPACTION ZR in the data class.
Coexistence requirements:
- Support for creating compressed-format PDSEs are enabled if all systems within a sysplex are a z/OS V2R3 or z/OS V2R4 system with OA61168, or a later system.
Types of Compression:
Compressed-format PDSEs utilize zEDC compression. For more information on this type of compression, see Types of Compression.
Characteristics of Compressed-Format PDSEs:
Most characteristics which apply to PDSEs continue to apply to compressed-format PDSEs. However,
due to the differences in data format, the following characteristics further describe
compressed-format PDSEs:
- Compression within a compressed-format PDSE occurs at the member level. An individual member might not be compressed if it does not meet system-determined criteria.
- Directory entries are not compressed.
- A member within a compressed-format PDSE cannot be opened for update.
- While a program object can be added to a compressed-format PDSE, program objects are not compressed.
Restrictions:
- Compressed-format PDSEs must be SMS-managed.
- Temporary data sets cannot be allocated as compressed-format PDSEs.
![End of change](./deltaend.gif)