4.7 SRTF Scheduling Algorithm (Preemptive SJF) | Step-by-Step

4.7 SRTF Scheduling Algorithm (Preemptive SJF) | Step-by-Step Shortest Remaining Time First (SRTF) scheduling is a CPU scheduling algorithm in Operating Systems (OS) and is the preemptive version of Shortest Job First (SJF). In SRTF, the CPU always selects the process with the smallest remaining execution time. Unlike non-preemptive SJF, this algorithm allows preemptive scheduling, meaning a currently running process can be interrupted if a new process with a shorter burst time arrives. This makes SRTF highly dynamic and closely tied to concepts like context switching, process scheduling, and ready queue management in OS. Through a step-by-step example, SRTF scheduling continuously re-evaluates processes based on their remaining time, not just initial burst time. Whenever a new process enters the system, the OS compares it with the running process and switches if needed. This behavior helps minimize average waiting time and improves system responsiveness, making SRTF one of the most optimal CPU scheduling algorithms in theory. It is commonly explained using Gantt charts, waiting time, and turnaround time calculations in OS tutorials. However, SRTF also has limitations. Due to its preference for shorter processes, it can cause starvation in OS, where longer processes are delayed indefinitely if shorter jobs keep arriving. Frequent preemption also increases context switching overhead, affecting system performance. While SRTF scheduling is excellent for efficiency, it lacks fairness, which is why alternatives like Round Robin scheduling and Priority scheduling are often used in real-world systems. For Private Coaching Contact Us On WhatsApp: +91 9892614730 Website: https://www.shreelearningacademy.com Mail: [email protected] LinkedIn: https://www.linkedin.com/company/shree-learning-academy/ Instagram : https://www.instagram.com/shreelearningacademy/ Twitter: https://twitter.com/ShreeLearning Facebook: https://fb.me/shreelearningacademy #OperatingSystem #OSTutorial #TechnologyExplained #ComputerScience #OSConcepts #TechEducation