What work is
On your System i™ product, work is always being done, whether you initiate it or the system initiates it. Any action done on the system has some type of work being performed to complete it.
Work is done when you turn on your system, when you open a file, or when you query a database. Each piece of work on the system is performed by a job. A job can be as simple as an application that waits for a user to call it or it can be as complex as a constantly running system query that monitors the number of users on the system every hour. Some jobs, specifically batch and interactive jobs, have job descriptions associated with them that tell when and where the job will run.
Jobs are made up of programs that perform certain functions. There is no limit to the amount of functions a job performs. A job contains the step-by-step instructions that must be completed for work to be done. The programs that make up the job run in a specific order. (For example, program A needs to run before program B can begin.) Threads help a job complete its work. An active job contains at least one thread. When a job contains multiple threads, it has the ability to do more than one thing at once. For example, one thread can go out and do calculations while another thread waits for more data to process.
Parent topic:
How work gets doneRelated concepts
What happens before work enters the system How work enters the system How work gets processed How work leaves the system