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FCFS Scheduling Calculator
Non-preemptive CPU scheduling. Processes run in order of arrival.
| PID | Arrival | Burst |
|---|
What is FCFS Scheduling?
FCFS (First Come First Serve) is a CPU scheduling algorithm. Processes are executed in the order they arrive in the ready queue.
Is FCFS Preemptive or Non-Preemptive?
FCFS (First Come First Serve) is a non-preemptive CPU scheduling algorithm. Once a process starts running, it continues until it finishes. The CPU is then assigned to the next process in the order it arrived.
How FCFS Works
The process that arrives first gets the CPU first. After it finishes, the next available process is executed. This continues until all processes are completed.
FCFS Scheduling Formulas
Turnaround Time = Completion Time − Arrival Time
Waiting Time = Turnaround Time − Burst Time
Advantages and Disadvantages of FCFS
| Advantages of FCFS | Disadvantages of FCFS |
|---|---|
| Simple and easy to implement. | It is a non-preemptive algorithm. |
| Processes are handled in arrival order. | Short processes can wait behind long processes. |
| Easy to understand using a queue. | It can cause the convoy effect. |
Related CPU Scheduling Calculators
Try the SJF Calculator, Round Robin Calculator, or Priority Scheduling Calculator .