Round Robin Scheduling Example With Gantt Chart Pdf
Introduction to Round Robin Scheduling
Round Robin Scheduling is a popular algorithm used in Operating Systems for scheduling processes. It is a pre-emptive algorithm, which means that the CPU can be taken away from a process and given to another process when a pre-defined time quantum expires. The algorithm is simple and easy to implement, making it a popular choice in many operating systems.
How Round Robin Scheduling Works
The Round Robin Scheduling algorithm works by assigning a fixed time quantum to each process. When a process is scheduled, it is allowed to run for the time quantum. If the process completes its execution within the time quantum, it is removed from the CPU. If the process does not complete its execution within the time quantum, it is pre-empted and moved to the end of the ready queue. The next process in the ready queue is then scheduled to run for the time quantum.
Round Robin Scheduling Example with Gantt Chart
Let's consider an example to understand the Round Robin Scheduling algorithm better. Suppose we have three processes P1, P2, and P3, with their respective arrival times and burst times as shown in the table below:
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 5 |
| P2 | 1 | 3 |
| P3 | 2 | 4 |
Let's assume that the time quantum for the Round Robin Scheduling algorithm is 2 units. We can represent the execution of these processes using a Gantt Chart. The Gantt Chart for this example is shown below:
As we can see from the Gantt Chart, each process is given 2 units of time quantum to execute. If a process completes its execution within the time quantum, it is removed from the CPU. If the process does not complete its execution within the time quantum, it is pre-empted and moved to the end of the ready queue. The next process in the ready queue is then scheduled to run for the time quantum.
Advantages and Disadvantages of Round Robin Scheduling
The Round Robin Scheduling algorithm has several advantages, including:
- It is simple and easy to implement
- It ensures fairness in CPU allocation, as each process is given a fixed time quantum
- It is good for interactive systems, as it allows processes to be executed in a timely manner
However, the Round Robin Scheduling algorithm also has some disadvantages, including:
- It may not be suitable for real-time systems, as processes may not complete their execution within the time quantum
- It may result in a high context switch overhead, as processes are constantly being pre-empted and moved to the end of the ready queue
- It may result in low CPU utilization, as processes may not require the full time quantum to complete their execution
Conclusion
The Round Robin Scheduling algorithm is a popular algorithm used in Operating Systems for scheduling processes. It is a pre-emptive algorithm that assigns a fixed time quantum to each process. The algorithm is simple and easy to implement, making it a popular choice in many operating systems. However, it also has some disadvantages, including high context switch overhead and low CPU utilization. As with any algorithm, it is important to consider the specific requirements of the system before choosing the Round Robin Scheduling algorithm.
