Subsystem definition

Edit the IEFSSNnn member in the SYS1.PARMLIB library, where nn is the suffix specified in the IEASYS member in the SYS1.PARMLIB library. If the suffix is not specified in the IEASYS, the default is 00. The subsystem can be defined using positional or keyword parameter structure.

• When using the keyword parameter structure, add a record to the IEFSSNnn member in the following format:

  SUBSYS SUBNAME(xxxx)

where xxxx is the name of the subsystem

• When using the positional parameter structure, add a record to the IEFSSNnn member in the following format:

  xxxx

where xxxx is the name of the subsystem

INCONTROL subsystems are initialized when their corresponding monitors are started. There is no need to define them in the IEFSSNnn member.

They can be defined in IEFSSNnn member without specifying a subsystem initialization routine.

If INCONTROL subsystems are defined, their position in the IEFSSNnn member is not important (see Special considerations for Control-O).

INCONTROL subsystems are not affected by the BEGINPARALLEL statement, which might appear in IEFSSNnn, because INCONTROL subsystems have no subsystem initialization routines and the BEGINPARALLEL statement indicates that the subsystem initialization routines specified in SUBSYS statements that follow the BEGINPARALLEL statement are invoked in parallel.      

For more information, see the relevant IBM MVS Initialization and Tuning Reference.