In data processing , a job refers to a single, closed job to be executed in the background by the operating system.
A job used to correspond to processing that was controlled by a single stack of punched cards .
On IBM mainframes running the z / OS operating system , jobs are interpreted by a so-called Job Entry Subsystem (JES2 or JES3) and then run in an already prepared address space , an initiator . The control within a job is in the scripting language Job Control Language written (JCL). One batch ( batch ) consists of a whole job net , wherein the individual jobs have mutual dependencies, and is usually connected to a control software such as OPC or CTL / M controlled.
IBM AS / 400
- a batch job that was initiated by a real or virtual stack of cards in the job input queue , or
- an interactive command under the Intercom timeshare system that is processed by a program or requires operator interaction,
- a multi-user job (MUJ) that serves several interactive users in parallel, or
- an operator command assigned to a control point , such as B. Janus or Mfstat or any program in a system library .
The term job is also used in Unix shells for processes for which certain management options exist (job control) .
In connection with computing grids , a job refers to a computation order that is transferred to the grid.