Operating System Scheduling by Hand: FCFS, Shortest Job First, Round Robin, Priorities, Page Replacement & Disk Scheduling
See how a computer decides what runs next. You will schedule processes first-come-first-served, shortest first, by priority and round robin, compute waiting and turnaround times, simulate page replacement with FIFO, LRU and the optimal rule, count page faults and compare disk scheduling orders, with every cell checked as you go.
One-time payment · lifetime access · lessons, labs, exam and certificate included · no subscription.
About this course
This course shows how an operating system decides what happens next by letting you do the scheduler's work yourself. You calculate turnaround and waiting times and CPU utilisation, schedule jobs first-come-first-served with MAX and build a text timeline with XLOOKUP, rank jobs for shortest job first with a tie-break, compute priority start times with SUMIF and apply an ageing rule against starvation. You step through round robin with a time quantum and count context switches, mark hits and faults for FIFO page replacement, find last and next uses for LRU and the optimal rule, meet Belady's anomaly and compare the total head movement of FCFS, shortest seek and the elevator order.
Lessons
- Processes & Metrics: Arrival, Burst, Turnaround, Waiting and CPU Utilisation Pro
- First-Come, First-Served: Start Times, Idle Gaps, a Timeline and the Convoy Effect Pro
- Shortest Job First: Ranking Bursts, Breaking Ties and Beating FCFS on Waiting Time Pro
- Priority Scheduling: Start Times with SUMIF, Starvation and a Simple Ageing Rule Pro
- Round Robin: Time Quantum, Remaining Burst per Round, Context Switches and Quantum Size Pro
- Page Replacement with FIFO: Reference Strings, Frames, Hits, Faults and the Fault Rate Pro
- LRU and Optimal Replacement: Last Use, Next Use, Victims and Belady's Anomaly Pro
- Disk Scheduling: FCFS, Shortest Seek First and the Elevator Order with Total Head Movement Pro