[z/OS]

Preparing IBM MQ for z/OS to use the zEnterprise Data Compression Express facility

The zEnterprise® Data Compression (zEDC) Express facility is available for certain models of IBM® machines, starting from IBM zEC12 GA2, using a minimum z/OS® level of z/OS 2.1.

See zEnterprise Data Compression (zEDC) for further information.

Prerequisites

For IBM z15 and later, the zEnterprise Data Compression (zEDC) Express facility was moved from an optional feature in the PCIe I/O drawer of the hardware system to be on-chip as the Integrated Accelerator for zEDC. With this change, the configuration prerequisites are updated and are dependent on your hardware system.

IBM z15 or later

Apply one of the following PTFs, according to your level of z/OS:
  • z/OS 2.4: UJ00636
  • z/OS 2.3: UJ00635
  • z/OS 2.2: UJ00638
  • z/OS 2.1: UJ00639

There are no hardware requirements for z15 or later systems. The Integrated Accelerator for zEDC solution in these systems provides built-in data acceleration, so a separate adapter is no longer required.

IBM zEC12 GA2 to IBM z14

Your system must also have the following requirements:
  • A zEDC Express® adapter, installed in the PCIe I/O drawers of the hardware system.
  • The zEDC software capability (an optional, paid-for feature) must be enabled in an IFAPRDxx parmlib member.

Procedure

IBM zEC12 GA2 to IBM z14
Ensure that the channel initiator user ID has READ authority to the FPZ.ACCELERATOR.COMPRESSION profile in the RACF® FACILITY CLASS, or the equivalent in the external security manager (ESM) that your enterprise uses.
Attention: Not required for IBM z15 or later.
IBM zEnterprise zEC12 GA2 or later
Configure the channel with COMPMSG(ZLIBFAST) at both the sending and receiving ends. Once configured, zlib compression is used to compress and decompress messages flowing across the channel.
Compression is performed in the zEDC when the size of the data to be compressed is above the minimum threshold. The threshold is dependent upon the IBM z hardware being used
  • IBM zEC12 GA2 to IBM z14 has a minimum threshold of 4KB
  • IBM z15 or later has a minimum threshold of 1KB

For messages below the threshold size, compression or inflation is performed in the software.