Specifying the Number of CI DSPs in the JES3 Global Address Space

Use the STANDARDS initialization statement to specify the maximum number of copies of the CI DSP that can operate in the JES3 global address space at any time. The CICNT parameter defines the maximum number of CI DSPs that can process (1) batch and (2) demand select (started task and TSO LOGON) jobs. The combined maximum number of CI DSPs active in the JES3 global address space at any time cannot exceed 255.

If you specify CICNT=(0,0), no CI DSPs will run in the JES3 global address space. If you do not specify the CICNT parameter, JES3 defines 2 C/I DSPs assigned to batch jobs and 1 CI DSP assigned to demand select jobs.

To determine how many CI DSPs to run in the JES3 global address space, consider how much private area virtual storage is available in that address space. CI DSPs for demand select jobs use less SWA space than CI DSPs for batch jobs because demand select jobs normally have fewer JCL statements. If private area virtual storage is constrained, define demand select CI DSPs but no batch CI DSPs.

Note: If you define C/I FSS address spaces for your installation, JES3 creates a special C/I subtask in the JES3 global address space for starting C/I FSS address spaces; it cannot be used for starting other tasks or TSO LOGONs. This subtask allows a C/I FSS address space to be started even if you specify CICNT=(0,0) in the initialization stream. The DSP counts for the JES3 global address space do not include this subtask, but you should account for the subtask when determining how much private area virtual storage is available.