A job's life

 

To understand the basics of System i™ work management, follow a simple batch job as it moves through the system.

The life of a simple batch job begins when you submit it to the system. The job is then sent to a job queue where it waits to enter a subsystem where it can run. After the job moves to the subsystem it is allocated memory in which to run. The printer output file (also called spooled files) is then sent to the output queue to await further instruction on what to do (for example, printing). While not every job follows this exact path, you can better understand how other work is completed on the system by learning more about this typical job life cycle.

Submit the job > Job enters the job queue > Job enters the subsystem > The memory pool allocates memory to the subsystem > The job finishes and moves to the output queue

  1. Submitting a job
    When a job is submitted, it is created and enters the system. At this time, the attributes are given to the job.
  2. The job enters the job queue
    Job queues are work entry points for batch jobs to enter the system. They can be thought of as "waiting rooms" for a subsystem.
  3. The job enters the subsystem
    Subsystems are operating environments where the system manages the resources that jobs use and controls the jobs that run within them. After jobs are running in the subsystem, the subsystem job carries out user requests on a job such as holding, releasing, and ending a job. When the job enters the subsystem it becomes active.
  4. The subsystem uses memory from the memory pool to run the job
    Memory is a resource from the memory pool that the subsystem uses to run the job. The amount of memory in a memory pool, as well as how many other jobs are competing for memory, affect how efficiently a job runs.
  5. The job finishes and moves to the output queue
    A job's printer output (also called spooled files) is sent to an output queue where it waits to be sent to a printer or file. The output queue is similar to the job queue in that it controls how the output is made available to the printer. The output queue allows the user to control what files are printed first.

 

Parent topic:

Introduction to work management