GATE - 2017 | OS | Consider the following CPU processes with arrival times
Posted on 08-02-2022
GATE - 2017 [Operating System]
Question:
Consider the following CPU processes with arrival times (in milliseconds) and length of CPU bursts (in milliseconds) as given below:
If the pre-emptive shortest remaining time first scheduling algorithm is used to schedule the processes, then the average waiting time across all processes is __________ milliseconds.
| A |
3 |
| B |
4 |
|
C |
5 |
|
D |
6 |
Solution 1:
Option (A) is Correct
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Solution 2:
Turn Around Time
P1 = 12-0 = 12P2 = 6-3 = 3P3 = 17-5 = 12P4 = 8 - 6 = 2
Waiting Time
P1 = 12-7 = 5P2 = 3-3 = 0P3 = 12-5 = 7P4 = 2 - 2 = 0
Average Waiting time = (7+0+5+0)/4 = 3.0
Thank You