Scheduling Algorithm: Shortest Remaining Time First (Pre-emptive)
Gantt chart:
0 3 5 8 12 15 21
Formula:
Turnaround time = Completion time – Arrival time.
Process Table:
Process Name
|
Arrival Time (AT)
|
Execution Time (ET)
|
Completion Time (CT)
|
Turnaround time
(TAT)
|
A
|
0
|
6
|
8
|
8
|
B
|
3
|
2
|
5
|
2
|
C
|
5
|
4
|
12
|
7
|
D
|
7
|
6
|
21
|
14
|
E
|
10
|
3
|
15
|
5
|
Average turnaround time = \(\frac{{\left( {8\; + \;2\; + \;7\; + \;14\; + \;5} \right)}}{5} = 7.2\;msec\)
Important Points:
TAT = CT - AT