What is an SRB?

An SRB is a control block that represents a routine that performs a particular function or service in a specified address space. An SRB is similar to a TCB in that it identifies a unit of work to the system. Some characteristics of an SRB are:
  • An SRB cannot “own” storage areas. SRB routines can obtain, reference, use, and free storage areas, but the areas must be owned by a TCB.
  • An SRB has associated with it such resources as a dispatchable unit access list (DU-AL), a functional recovery routine (FRR) stack, a linkage stack, and a CPU timer value.

The routine that performs the function or service is called the SRB routine; initiating the process is called scheduling an SRB.

Parent topic: Using a service request block (SRB)