1. What Is First-Come-First-Served Scheduling?

First-Come-First-Served (FCFS) is one of the simplest CPU scheduling algorithms where processes are executed in the order they arrive in the ready queue. It is a non-preemptive scheduling algorithm that follows the principle of "first in, first out".

2. How Does The Calculator Work?

The calculator uses the FCFS completion time formula:

Where:

• \( Arrival\ Time \) — Time when the process arrives in the ready queue
• \( Burst\ Time \) — Time required by the process for CPU execution
• \( Completion\ Time \) — Time when the process completes its execution

Explanation: In FCFS scheduling, each process gets the CPU in the order of arrival. The completion time is simply the sum of arrival time and burst time for each process.

3. Importance Of Completion Time Calculation

Details: Calculating completion time is essential for determining other performance metrics like turnaround time, waiting time, and throughput. It helps in analyzing the efficiency of the scheduling algorithm and system performance.

4. Using The Calculator

Tips: Enter arrival time and burst time in time units. Both values must be valid (arrival time ≥ 0, burst time > 0). The calculator will compute the completion time automatically.

5. Frequently Asked Questions (FAQ)

Q1: What Is The Main Characteristic Of FCFS Scheduling?
A: FCFS is non-preemptive and processes are executed in the exact order of their arrival, making it simple but potentially inefficient due to the convoy effect.

Q2: How Does FCFS Handle Multiple Processes?
A: For multiple processes, the completion time of each process depends on the completion time of the previous process in the queue plus its own burst time.

Q3: What Is The Convoy Effect In FCFS?
A: The convoy effect occurs when short processes wait for a long process to complete, leading to poor utilization of resources and increased average waiting time.

Q4: Is FCFS Suitable For Time-Sharing Systems?
A: No, FCFS is not suitable for time-sharing systems because it doesn't provide good response time. It's better suited for batch systems.

Q5: How Is Turnaround Time Calculated In FCFS?
A: Turnaround time = Completion Time - Arrival Time. It represents the total time taken from arrival to completion of the process.