FCFS Algorithm With Arivall Time

In this example, we analyze the arrival time of the FCFS algorithm.

Arrival Time	Burst Time	Process
3	10	P1
1	5	P2
0	20	P3
1	10	P4

P1

P4

P2

P3

CPU

 FCFS     P3            p2          p4          p1

CPU |-----------|-----------|-----------|-----------|

       0           20           25          35          45

TA  = Time End Process – (Arrival Time)

TA₁= 45 – 3 = 42

TA₂= 25 – 1 = 24

                            TA Average           è  120/4 = 30

TA₃= 20 – 0 = 20

TA₄= 35 – 1 = 34

WT = Wait Time Process – (Arrival Time)

WT₁ = 35 – 3 =  32

WT₂ = 20 – 1 = 19

                              WT Average           è   75/4 = 18.75                  

WT₃ = 0 – 0 = 0

WT₄ = 25 – 1 = 24