FCFS - CPU SCheduling.pptx

FCFS

1. CPU SCHEDULING ALGORITHM - FCFS Dr. R.H. Aswathy

2. AGENDA What is scheduling? Types FCFS Example Calculation of Turnaround and W aiting time

3. CPU SCHEDULING ALGORITHMS

4. Various Times – CPU Scheduling

5. FCFS The process that comes first will be executed first and next process starts only after the current process is completed.

6. Calculation of Turn around time Turn Around Time = Completion Time – Arrival Time P1 = 10 – 0 = 10 P2 = 15 – 3 = 12 P3 = 17 – 5 = 12 P4 = 23 – 6 = 17 P5 = 27 – 8 = 19 Average turnaround time = 10 +12 + 12 + 17 + 19= 70/5= 14

7. Calculation of Waiting time Waiting Time = Turn Around Time – Burst Time P1 = 10 – 10 = 0 P2 = 12 – 5 = 7 P3 = 12 – 2 = 10 P4 = 17 – 6 = 11 P5 = 19 – 4 = 15 Average Waiting time = + 7 + 10 + 11 + 15 = 43/5 = 8.6

8. THANK YOU