JOB CONTROL

The JOB_CONTROL process is the VMS Job controller process.

Image Location: SYS$COMMON:[SYSEXE]JBC$JOB_CONTROL.EXE

Job controller process functional summary

The job controller performs multiple functions for VMS:

1. When a new terminal connection is detected the job controller creates a process attached to the terminal running LOGINOUT.EXE to initiate the login process.
2. Processes all VMS requests to write accounting data to the system accounting file.
3. Acts as the client communication to all VMS Queue Managers running in a cluster.
   1. Creates batch processes and symbiont processes on the local system.
   2. Notifies queue managers of the batch job and symbiont processes terminations on the local system.
   3. Creates queue manager processes for queue managers that are prioritized to run on the local system.
4. Performs Standard Time and Daylight Saving Time clock adjustments, when the system parameter AUTO_DLIGHT_SAV is 1.
5. As a known, persistent process JOB_CONTROL is sometimes used by products and OS components as the target to queue ASTs to perform a desired actions. For example, the Availability Manager Product has an option to force crash a system. The Availability Manager RMDRIVER queues an AST to the JOB_CONTROL process to perform the crash.

Job controller communication

The job controller receives messages to perform operations through two methods:

1. Job Control permanent Mailbox MBA1:
2. IPC Queue Manangement Association Channel <association name to be supplied>