Routing entries

The routing entry identifies the main storage subsystem pool to use, the controlling program to run (typically the system-supplied program QCMD), and additional run-time information (stored in the class object). Routing entries are stored in the subsystem description.

A routing entry can be likened to a single entry in a shopping mall directory. Customers that cannot find the store they need may use a directory to help send them in the right direction. The same is true on the iSeries™ system. Routing entries guide the job to the correct place. Routing entries in a subsystem description specify the program to be called to control a routing step for a job running in the subsystem, which memory pool the job will use, and from which class to get the run-time attributes. Routing data identifies a routing entry for the job to use. Together, routing entries and routing data provide information about starting a job in a subsystem.

Routing entries consist of these parts; the subsystem description, class, comparison data, maximum active routing steps, memory pool ID, program to call, thread resources affinity, resources affinity group, and the sequence number.

• Class
  Job run-time attributes are contained in the class object that is specified in the (CLS) parameter in the routing entry. If a job consists of multiple routing steps, the class used by each subsequent routing step is specified in the routing entry used to start the routing step. If the class does not exist when the routing entry is added, a library qualifier must be specified because the qualified class name is kept in the subsystem description.
• Comparison data
  The comparison value (CMPVAL) parameter of the routing entry specifies data that is compared with routing data to determine which routing entry to use. (The routing entry also specifies the starting position for the comparison.) The routing data is compared with the comparison value of each routing entry in sequence number order until a match is found. The sequence number contained in a routing entry defines the order in which the routing entries are scanned and can be used as the identifier of the routing entry.
• Maximum active routing steps
  The maximum active routing steps (MAXACT) parameter of the routing entry specifies the maximum number of routing steps (jobs) that can be active at the same time through this routing entry.
• Memory pool ID
  The memory pool ID (POOLID) parameter of the routing entry specifies the pool identifier of the storage pool in which the program runs. The pool identifier specified here relates to the storage pools in the subsystem description.