Scheduler

A scheduler is the software module in a multi-tasking system (such as an operating system with processes) which decides which computation is to run next when the previous computation gives up (or is forced off, in preemptive multi-tasking) the processor.

There are many different types of scheduler.

In a large time-sharing system, users are often organized into groups, and the system administrator may be able to set things so that particular groups are guaranteed minimum shares of the machine.

In a real-time system, a scheduler known as a 'deadline scheduler' may be supported; each task sets a time by which is must run, and the scheduler selects tasks to run in order of their deadlines.