Job processing cycle
Encyclopedia
In mainframe
operating system
s, when a job is submitted, the operating system takes the job through a series of steps known as the job processing cycle. A large number of jobs is usually executed in a given time period, such as night, which is a scheme historically known as batch processing
. Regardless of the job stream
that a given job will follow, its processing cycle always contains the same sequence of steps: the steps involved in the job processing cycle include: sourceing of the data, arranging the sourced data in order to avoid erratic or typographic error, inputing the arranged data into the computer for processing, outputing of the processed data inform of information, and lastly is the transmission of the information to where it will be useful. this transmitted information can also serve as a source data for further processing that is why it is called the job processing cycle.
Mainframe computer
Mainframes are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing.The term originally referred to the...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s, when a job is submitted, the operating system takes the job through a series of steps known as the job processing cycle. A large number of jobs is usually executed in a given time period, such as night, which is a scheme historically known as batch processing
Batch processing
Batch processing is execution of a series of programs on a computer without manual intervention.Batch jobs are set up so they can be run to completion without manual intervention, so all input data is preselected through scripts or command-line parameters...
. Regardless of the job stream
Job stream
In an IBM mainframe, the job stream is the path of execution that a job follows. The JCL and any data submitted with it form the job stream. There can be multiple EXEC and DD statements in a job stream if a job involves more than one program....
that a given job will follow, its processing cycle always contains the same sequence of steps: the steps involved in the job processing cycle include: sourceing of the data, arranging the sourced data in order to avoid erratic or typographic error, inputing the arranged data into the computer for processing, outputing of the processed data inform of information, and lastly is the transmission of the information to where it will be useful. this transmitted information can also serve as a source data for further processing that is why it is called the job processing cycle.
- Job submission – entering job parameters to the operating system with a scripting language, such as JCLJob Control LanguageJob Control Language is a scripting language used on IBM mainframe operating systems to instruct the system on how to run a batch job or start a subsystem....
, usually contained in a data setData set (IBM mainframe)data set , dataset , is a computer file having a record organization. The term pertains to the IBM mainframe operating system line, starting with OS/360, and is still used by its successors, including the current z/OS. Those systems historically preferred this term over a file...
or historically on punched cardPunched cardA punched card, punch card, IBM card, or Hollerith card is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions...
s - Job reading – operating system parses JCL data set
- Job spoolingSpoolingIn computer science, spool refers to the process of placing data in a temporary working area for another program to process. The most common use is in writing files on a magnetic tape or disk and entering them in the work queue for another process. Spooling is useful because devices access data at...
- Job selection
- Job execution with output spoolingSpoolingIn computer science, spool refers to the process of placing data in a temporary working area for another program to process. The most common use is in writing files on a magnetic tape or disk and entering them in the work queue for another process. Spooling is useful because devices access data at...
– executing actual computer programComputer programA computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...
s included in a job and collecting their output - Job output (print or punch)
- Job purge – All resources associated with the job are released.