There are three types of process scheduler.
1. Long Term or job scheduler It bring the new process to the ‘Ready State’. It controls Degree of Multi-programming, i.e., number of process present in ready state at any point of time.
2. Short term ot CPU scheduler: It is responsible for selecting one process from ready state for scheduling it on the running state. Note: Short term scheduler only selects the process to schedule it doesn’t load the process on running.
[ad type=”banner”] Dispatcher is responsible for loading the selected process by Short Term scheduler on the CPU (Ready to Running State) Context switching is done by dispatcher only. A dispatcher does following:1) Switching context.
2) Switching to user mode.
3) Jumping to the proper location in the newly loaded program. [ad type=”banner”]
3. Medium term scheduler It is responsible for suspending and resuming the process. It mainly does swapping (moving processes from main memory to disk and vice versa).
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