Question 11: Non-preemptive SJF Scheduling
find the average Turn Around Time and Waiting Time of following processes using Non-Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 6 |
| P2 | 2 | 4 |
| P3 | 4 | 3 |
| P4 | 6 | 5 |
| P5 | 8 | 2 |
Solution :
Formulas:
- Turn Around Time (TAT) = Completion Time (CT) - Arrival Time (AT)
- Waiting Time (WT) = Turn Around Time (TAT) - Burst Time (BT)
Gantt Chart
| P1 (0-6) | P3 (6-9) | P5 (9-11) | P2 (11-15) | P4 (15-20) |
| Process | Arrival Time | Burst Time | Completion Time | Turn Around Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 6 | 6 | 6 | 0 |
| P2 | 2 | 4 | 15 | 13 | 9 |
| P3 | 4 | 3 | 9 | 5 | 2 |
| P4 | 6 | 5 | 20 | 14 | 9 |
| P5 | 8 | 2 | 11 | 3 | 1 |
Formula for average TAT and WT:
- Average Turn Around Time (Average TAT) = Σ(TAT) / Number of Processes
- Average Waiting Time (Average WT) = Σ(WT) / Number of Processes
Average Turn Around Time (TAT) = (6+13+5+14+3)/5 = 8.2 units
Average Waiting Time (WT) = (0+9+2+9+1)/5 = 4.2 units
Question 12: Preemptive SJF Scheduling
find the average Turn Around Time and Waiting Time of following processes using Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 7 |
| P2 | 2 | 4 |
| P3 | 3 | 9 |
| P4 | 5 | 3 |
| P5 | 6 | 5 |
Solution :
Formulas:
- Turn Around Time (TAT) = Completion Time (CT) - Arrival Time (AT)
- Waiting Time (WT) = Turn Around Time (TAT) - Burst Time (BT)
Gantt Chart
| P1 (0-2) | P2 (2-6) | P4 (6-9) | P1 (9-14) | P5 (14-19) | P3 (19-28) |
| Process | Arrival Time | Burst Time | Completion Time | Turn Around Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 7 | 14 | 14 | 7 |
| P2 | 2 | 4 | 6 | 4 | 0 |
| P3 | 3 | 9 | 28 | 25 | 16 |
| P4 | 5 | 3 | 9 | 4 | 1 |
| P5 | 6 | 5 | 19 | 13 | 8 |
Formula for average TAT and WT:
- Average Turn Around Time (Average TAT) = Σ(TAT) / Number of Processes
- Average Waiting Time (Average WT) = Σ(WT) / Number of Processes
Average Turn Around Time (TAT) = (14+4+25+4+13)/5 = 12 units
Average Waiting Time (WT) = (7+0+16+1+8)/5 = 6.4 units
Question 13: Non-preemptive SJF Scheduling
find the average Turn Around Time and Waiting Time of following processes using Non-Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 8 |
| P2 | 1 | 4 |
| P3 | 2 | 9 |
| P4 | 3 | 5 |
| P5 | 4 | 3 |
Solution :
Formulas:
- Turn Around Time (TAT) = Completion Time (CT) - Arrival Time (AT)
- Waiting Time (WT) = Turn Around Time (TAT) - Burst Time (BT)
Gantt Chart
| P1 (0-8) | P5 (8-11) | P2 (11-15) | P4 (15-20) | P3 (20-29) |
| Process | Arrival Time | Burst Time | Completion Time | Turn Around Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 8 | 8 | 8 | 0 |
| P2 | 1 | 4 | 15 | 14 | 10 |
| P3 | 2 | 9 | 29 | 27 | 18 |
| P4 | 3 | 5 | 20 | 17 | 12 |
| P5 | 4 | 3 | 11 | 7 | 4 |
Formula for average TAT and WT:
- Average Turn Around Time (Average TAT) = Σ(TAT) / Number of Processes
- Average Waiting Time (Average WT) = Σ(WT) / Number of Processes
Average Turn Around Time (TAT) = (8+14+27+17+7)/5=14.6 units
Average Waiting Time (WT) = (0+10+18+12+4)/5 = 8.8 units
Question 14: Preemptive SJF Scheduling
find the average Turn Around Time and Waiting Time of following processes using Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 5 |
| P2 | 1 | 2 |
| P3 | 3 | 4 |
| P4 | 4 | 3 |
| P5 | 5 | 6 |
Solution :
Formulas:
- Turn Around Time (TAT) = Completion Time (CT) - Arrival Time (AT)
- Waiting Time (WT) = Turn Around Time (TAT) - Burst Time (BT)
Gantt Chart
| P1 (0-1) | P2 (1-3) | P1 (3-7) | P4 (7-10) | P3 (10-14) | P5 (14-20) |
| Process | Arrival Time | Burst Time | Completion Time | Turn Around Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 5 | 7 | 7 | 2 |
| P2 | 1 | 2 | 3 | 2 | 0 |
| P3 | 3 | 4 | 14 | 11 | 7 |
| P4 | 4 | 3 | 10 | 6 | 3 |
| P5 | 5 | 6 | 20 | 15 | 9 |
Formula for average TAT and WT:
- Average Turn Around Time (Average TAT) = Σ(TAT) / Number of Processes
- Average Waiting Time (Average WT) = Σ(WT) / Number of Processes
Average Turn Around Time (TAT) = (7+2+11+6+15)/5 = 8.2 units
Average Waiting Time (WT) = (2+0+7+3+9)/5 = 4.2 units
Question 15: Non-preemptive SJF Scheduling
find the average Turn Around Time and Waiting Time of following processes using Non-Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 10 |
| P2 | 1 | 1 |
| P3 | 2 | 2 |
| P4 | 3 | 1 |
| P5 | 4 | 5 |
Solution :
Formulas:
- Turn Around Time (TAT) = Completion Time (CT) - Arrival Time (AT)
- Waiting Time (WT) = Turn Around Time (TAT) - Burst Time (BT)
Gantt Chart
| P1 (0-10) | P2 (10-11) | P4 (11-12) | P3 (12-14) | P5 (14-19) |
| Process | Arrival Time | Burst Time | Completion Time | Turn Around Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 10 | 10 | 10 | 0 |
| P2 | 1 | 1 | 11 | 10 | 9 |
| P3 | 2 | 2 | 14 | 12 | 10 |
| P4 | 3 | 1 | 12 | 9 | 8 |
| P5 | 4 | 5 | 19 | 15 | 10 |
Formula for average TAT and WT:
- Average Turn Around Time (Average TAT) = Σ(TAT) / Number of Processes
- Average Waiting Time (Average WT) = Σ(WT) / Number of Processes
Average Turn Around Time (TAT) = (10+10+12+9+15)/5 = 11.2 units
Average Waiting Time (WT) = (0+9+10+8+10)/5 = 7.4 units
Question 16: Non-Preemptive SJF
find the average Turn Around Time and Waiting Time of following processes using Non-Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 7 |
| P2 | 2 | 4 |
| P3 | 4 | 1 |
| P4 | 5 | 4 |
| P5 | 6 | 3 |
Solution :
Formulas:
- Turnaround Time (TAT) = Completion Time - Arrival Time
- Waiting Time (WT) = Turnaround Time - Burst Time
Gantt Chart
| P1 (0-7) | P3 (7-8) | P5 (8-11) | P2 (11-15) | P4 (15-19) |
| Process | Arrival Time | Burst Time | Completion Time | Turnaround Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 7 | 7 | 7 - 0 = 7 | 7 - 7 = 0 |
| P2 | 2 | 4 | 15 | 15 - 2 = 13 | 13 - 4 = 9 |
| P3 | 4 | 1 | 8 | 8 - 4 = 4 | 4 - 1 = 3 |
| P4 | 5 | 4 | 19 | 19 - 5 = 14 | 14 - 4 = 10 |
| P5 | 6 | 3 | 11 | 11 - 6 = 5 | 5 - 3 = 2 |
Formulas for Average TAT and WT
- Average Turnaround Time = Sum of Turnaround Times / Number of Processes
- Average Waiting Time = Sum of Waiting Times / Number of Processes
Average TAT and WT
Average TAT = (7 + 13 + 4 + 14 + 5) / 5 = 43 / 5 = 8.6 units
Average WT = (0 + 9 + 3 + 10 + 2) / 5 = 24 / 5 = 4.8 units
Question 17: Preemptive SJF
find the average Turn Around Time and Waiting Time of following processes using Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 9 |
| P2 | 1 | 3 |
| P3 | 2 | 6 |
| P4 | 3 | 2 |
| P5 | 5 | 4 |
Solution :
Formulas:
- Turnaround Time (TAT) = Completion Time - Arrival Time
- Waiting Time (WT) = Turnaround Time - Burst Time
Gantt Chart
| P1 (0-1) | P2 (1-4) | P4 (4-6) | P5 (6-10) | P3 (10-16) | P1 (16-24) |
| Process | Arrival Time | Burst Time | Completion Time | Turnaround Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 9 | 24 | 24 - 0 = 24 | 24 - 9 = 15 |
| P2 | 1 | 3 | 4 | 4 - 1 = 3 | 3 - 3 = 0 |
| P3 | 2 | 6 | 16 | 16 - 2 = 14 | 14 - 6 = 8 |
| P4 | 3 | 2 | 6 | 6 - 3 = 3 | 3 - 2 = 1 |
| P5 | 5 | 4 | 10 | 10 - 5 = 5 | 5 - 4 = 1 |
Formulas for Average TAT and WT
- Average Turnaround Time = Sum of Turnaround Times / Number of Processes
- Average Waiting Time = Sum of Waiting Times / Number of Processes
Average TAT and WT
Average TAT = (24 + 3 + 14 + 3 + 5) / 5 = 49 / 5 = 9.8 units
Average WT = (16 + 0 + 8 + 1 + 1) / 5 = 26 / 5 = 5.2 units
Question 18: Non-Preemptive SJF
find the average Turn Around Time and Waiting Time of following processes using Non-Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 8 |
| P2 | 1 | 4 |
| P3 | 2 | 9 |
| P4 | 3 | 5 |
| P5 | 4 | 2 |
Solution :
Formulas:
- Turnaround Time (TAT) = Completion Time - Arrival Time
- Waiting Time (WT) = Turnaround Time - Burst Time
Gantt Chart
| P1 (0-8) | P5 (8-10) | P2 (10-14) | P4 (14-19) | P3 (19-28) |
| Process | Arrival Time | Burst Time | Completion Time | Turnaround Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 8 | 8 | 8 - 0 = 8 | 8 - 8 = 0 |
| P2 | 1 | 4 | 14 | 14 - 1 = 13 | 13 - 4 = 9 |
| P3 | 2 | 9 | 28 | 28 - 2 = 26 | 26 - 9 = 17 |
| P4 | 3 | 5 | 19 | 19 - 3 = 16 | 16 - 5 = 11 |
| P5 | 4 | 2 | 10 | 10 - 4 = 6 | 6 - 2 = 4 |
Formulas for Average TAT and WT
- Average Turnaround Time = Sum of Turnaround Times / Number of Processes
- Average Waiting Time = Sum of Waiting Times / Number of Processes
Average TAT and WT
Average TAT = (8 + 13 + 26 + 16 + 6) / 5 = 69 / 5 = 13.8 units
Average WT = (0 + 9 + 17 + 11 + 4) / 5 = 41 / 5 = 8.2 units
Question 19: Preemptive SJF
find the average Turn Around Time and Waiting Time of following processes using Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 10 |
| P2 | 1 | 3 |
| P3 | 2 | 7 |
| P4 | 3 | 4 |
| P5 | 5 | 5 |
Solution :
Formulas:
- Turnaround Time (TAT) = Completion Time - Arrival Time
- Waiting Time (WT) = Turnaround Time - Burst Time
Gantt Chart
| P1 (0-1) | P2 (1-4) | P4 (4-8) | P5 (8-13) | P3 (13-20) | P1 (20-29) |
| Process | Arrival Time | Burst Time | Completion Time | Turnaround Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 0 | 10 | 29 | 29 - 0 = 29 | 29 - 10 = 19 |
| P2 | 1 | 3 | 4 | 4 - 1 = 3 | 3 - 3 = 0 |
| P3 | 2 | 7 | 20 | 20 - 2 = 18 | 18 - 7 = 11 |
| P4 | 3 | 4 | 8 | 8 - 3 = 5 | 5 - 4 = 1 |
| P5 | 5 | 5 | 13 | 13 - 5 = 8 | 8 - 5 = 3 |
Formulas for Average TAT and WT
- Average Turnaround Time = Sum of Turnaround Times / Number of Processes
- Average Waiting Time = Sum of Waiting Times / Number of Processes
Average TAT and WT
Average TAT = (29 + 3 + 18 + 5 + 8) / 5 = 63 / 5 = 12.6 units
Average WT = (19 + 0 + 11 + 1 + 3) / 5 = 34 / 5 = 6.8 units
Question 20: Non-Preemptive SJF
find the average Turn Around Time and Waiting Time of following processes using Non-Preemptive SJF(SHORTEST JOB FIRST) process scheduling algorithm?
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 1 | 6 |
| P2 | 2 | 3 |
| P3 | 3 | 4 |
| P4 | 4 | 2 |
| P5 | 5 | 5 |
| P6 | 6 | 3 |
Solution :
Formulas:
- Turnaround Time (TAT) = Completion Time - Arrival Time
- Waiting Time (WT) = Turnaround Time - Burst Time
Gantt Chart
| no process(0-1) | P1 (1-7) | P4 (7-9) | P2 (9-12) | P6 (12-15) | P3 (15-19) | P5 (19-24) |
| Process | Arrival Time | Burst Time | Completion Time | Turnaround Time (TAT) | Waiting Time (WT) |
|---|---|---|---|---|---|
| P1 | 1 | 6 | 7 | 7 - 1 = 6 | 6 - 6 = 0 |
| P2 | 2 | 3 | 12 | 12 - 2 = 10 | 10 - 3 = 7 |
| P3 | 3 | 4 | 19 | 19 - 3 = 16 | 16 - 4 = 12 |
| P4 | 4 | 2 | 9 | 9 - 4 = 5 | 5 - 2 = 3 |
| P5 | 5 | 5 | 24 | 24 - 5 = 19 | 19 - 5 = 14 |
| P6 | 6 | 3 | 15 | 15 - 6 = 9 | 9 - 3 = 6 |
Formulas for Average TAT and WT
- Average Turnaround Time = Sum of Turnaround Times / Number of Processes
- Average Waiting Time = Sum of Waiting Times / Number of Processes
Average TAT and WT
Average TAT = (6 + 10 + 16 + 5 + 19 + 9) / 6 = 65 / 6 = 10.83 units
Average WT = (0 + 7 + 12 + 3 + 14 + 6) / 6 = 42 / 6 = 7 units