BMC Software subsystems for AR/CTL components

AR/CTL uses BMC Software standard subsystems for resource management. A major advantage of using subsystem architecture is that it reduces virtual storage requirements in user address spaces. AR/CTL uses two BMC Software subsystems—the BMC Primary Subsystem (BMCP) and the BMC Consolidated Subsystem (BCSS). For more information about the subsystems, see Administering.

BMCP

The BMCP establishes supervisory services for the BCSS and many BMC Software products. It allows interception of open, close, attach, and link requests in the system (AR/CTL enhanced processing is used for interception of enqueue and dequeue requests for remote VSAM access in AR/CTL for VSAM). Because BMC Software products share the BMCP, you need only one copy of the BMCP on an MVS system. All associated BMC Software products continue to operate normally even if the BMCP terminates; however, BMC Software recommends that you leave the BMCP running at all times.

During configuration of AR/CTL or other products that use the BMCP, the BMCP is set up to start at each IPL.

BCSS

The BCSS manages I/O to the registration data sets (collectively called the REGISET), manages APF-authorized functions, and performs processing for intercepted open, close, attach, and link requests.

The BCSS must be active on the MVS system where you want to execute application programs that use AR/CTL products and where you want to access records in the REGISET through the ISPF interface. During configuration of AR/CTL or other products that use the BCSS, the BCSS is set up to start at each IPL.

More than one BCSS can be active on an MVS system. One must be defined as the public BCSS; it is typically used for production work. Each of the others is defined as a private BCSS; a private BCSS is typically used for testing new releases of AR/CTL. A default BCSS can be designated for all AR/CTL products on each MVS. You use the BCSS identifier (BCSID) to identify the subsystem (and REGISET) you want to use.

Three AR/CTL components are available with the BCSS: the IMS component, the non IMS component, and the VSAM component. The non IMS component must be enabled to allow AR/CTL for Db2 and AR/CTL for VSAM to operate. The IMS component must be enabled to allow AR/CTL for IMS (and the AR/CTL BCF component) to operate. The VSAM component must be installed to allow AR/CTL to perform VSAM logging and dynamic backout.

You can use the AR/CTL Status Check utility (program AESUVBCS) to ensure that the required AR/CTL products, components, and functions are available for application program execution.