Operator Commands › Defining Multiple VTAM Cross-Memory Regions › Regions Grouped by Operating System Subsystem Name

Regions Grouped by Operating System Subsystem Name

Multiple VTAM regions are grouped under a four-character operating system subsystem name. The SUBSYS= cross-memory parameter specifies the subsystem name at the startup time of the cross-memory region.

Unless you specifically want to define separate multiple groups of VTAM regions, we suggest that you use the default SUBSYS parameter.

Note: If you specify SUBSYS=, all VTAM regions grouped under the same SUBSYS must be started with the same release/PTF level of the CA View, CA Deliver, and/or CA Balancing load libraries.

Important! If you change your release of CA View, CA Deliver, and/or CA Balancing and you specified a value in SUBSYS=, you must change the SUBSYS= cross-memory parameter and IPL to prevent CSA damage.

The control block sizes for CA View, CA Deliver, and/or CA Balancing are release-dependent and serious problems can result if you do not specify the correct release.

If you use the default parameter for SUBSYS, you will not have this problem because each release of CA View, CA Deliver, and/or CA Balancing defaults to the appropriate SUBSYS name.