Question

Which scheduling algorithm gives each process an equal share of CPU time?

• A. FIFO
• B. Round Robin
• C. Priority Scheduling
• D. Shortest Job Next

Hint:

Think of Round Robin as a group of people taking turns using a single tool. Each person gets to use the tool for a fixed amount of time (the time quantum) before passing it to the next person in line.

Answer 1

The Correct Option is B

Let's analyze the CPU scheduling algorithms:
(A) FIFO (First-In, First-Out): Also known as First Come First Served (FCFS). Processes are executed in the order they arrive. A long process arriving first can make shorter processes wait for a long time. It does not give an equal share of CPU time.
(B) Round Robin: This is a preemptive scheduling algorithm designed for time-sharing systems. Each process is assigned a fixed time slice (or quantum). It runs for that amount of time, and if it's not finished, it's preempted and placed at the back of the ready queue. This gives every process a recurring, equal opportunity to run on the CPU.
(C) Priority Scheduling: Processes are assigned priorities, and the process with the highest priority is executed first. This is inherently unequal.
(D) Shortest Job Next (SJN): The process with the shortest estimated execution time is run next. This is also inherently unequal, as longer jobs may have to wait indefinitely.
Therefore, Round Robin is the algorithm that gives each process an equal share of CPU time over a longer period.