scheduling

[priya mahajan]

what should be the criterion for selecting the quantum size in round-robin scheduling algorithm so that its performance is best?

[r035198x]

what should be the criterion for selecting the quantum size in round-robin scheduling algorithm so that its performance is best?

deepends on how much time on avg your activities take and what you want your response times to be.

[Cyberdyne]

Round-Robin Scheduling

The Round-Robin scheduling algorithm has a queue, similar to the First Come, First Serve algorithm. It is preemptive.

It allocates the CPU in time slices known as time quantum. A quantum is a fixed time period (say 10 microseconds, etc.), the CPU then allocates these quantum to processes. After a process spends its quantum executing on the CPU, it is preempted, and moved to the back of the queue, another quantum is assigned to the next process on the queue.

If the process releases the CPU before its quantum is up, it gets put on the ready queue, and the next process gets a time quantum to execute.

The performance of Round Robin algorithm is largely dependent on the size of the time quantum. If the size is too large, the system essentially turns into a First Come-First Serve, if the quantum size is too small; the system spends too much time doing context switching.

[radcaesar]

Try this,

http://www.theparticle.com/cs/bc/os/notes0005.html

;)