Introduction-to-CPU-Scheduling copy.pptx

Introduction-to-CPU-Scheduling ppt

1. Introduction to CPU Scheduling CPU scheduling is a fundamental operating system concept that determines the order in which processes are executed on the CPU. It is crucial for maximizing CPU utilization and ensuring fair and efficient resource allocation. Done by P.Rama satwik reddy 227Z1A6749

2. First-Come, First-Served (FCFS) Scheduling 1 Process Arrival Processes are executed in the order they arrive in the ready queue. 2 Simple Implementation FCFS is the simplest scheduling algorithm, as it doesn't require complex calculations. 3 Potential Starvation Short processes may have to wait for long-running processes, leading to potential starvation.

3. Shortest-Job-First (SJF) Scheduling Optimum Completion Time SJF aims to minimize the average waiting time by executing the shortest job first. Preemptive vs. Non-Preemptive SJF can be preemptive, where a new short job can interrupt a longer running job, or non-preemptive, where jobs run to completion. Prediction Challenge SJF requires predicting the length of each job, which can be difficult in practice.

4. Shortest Remaining Time First (SRTF) Scheduling Preemptive Approach SRTF is a preemptive version of SJF, where the currently running job is interrupted if a shorter job arrives. Improved Efficiency SRTF can achieve lower average waiting times and turnaround times compared to FCFS and SJF. Complexity Tradeoff SRTF requires more overhead to track the remaining time of each job.

5. Round-Robin (RR) Scheduling 1 Time Slicing RR assigns a fixed time slice to each process in a circular queue. 2 Fairness RR ensures that all processes get a fair share of CPU time, preventing starvation. 3 Context Switching Overhead RR introduces more context switches, which can impact overall system performance. 4 Time Slice Selection The choice of time slice duration is critical for balancing responsiveness and throughput.

6. Conclusion and Comparison of Algorithms Algorithm Trade-offs Each scheduling algorithm has its own strengths and weaknesses, and the choice depends on the specific system requirements. Practical Considerations In real-world systems, a combination of scheduling algorithms may be used to balance various performance metrics. Ongoing Research CPU scheduling remains an active area of research, with new algorithms and techniques being developed to address evolving system needs. Importance of Understanding A thorough understanding of CPU scheduling algorithms is crucial for designing and optimizing efficient operating systems.