design your example and give computation results of several cpu schedulers
process |
arrival time |
burst time |
priority |
|---|
P1 |
8 |
6 |
5 |
P2 |
6 |
3 |
4 |
P3 |
5 |
10 |
2 |
P4 |
0 |
8 |
3 |
P5 |
2 |
7 |
1 |
1.shortest job first scheduling
preemptive
average waiting time = ((11-8)+(8-6)+(24-5)+0+(17-2))/5 = 7.8s
non preemptive
average waiting time = ((11-8)+(8-6)+(24-5)+0+(17-2))/5 = 7.8s
2.shortest remaining time first scheduling
empreitive:
average waiting time = ((11-8)+(8-6)+(24-5)+0+(17-2))/5 = 7.8s
nonempretive:
average waiting time = ((11-8)+(8-6)+(24-5)+0+(17-2))/5 = 7.8s
3.priority scheduling
average waiting time = ((28-8)+(25-6)+(9-5)+(19-2)+(2-2))/5 = 12s
4.round robin scheduling
let the circle is 4 millionseconds
average waiting time = ((30-4-8)+(12-6)+(32-4*2-5)+(19-4-0)+(23-4-2))/5 = 15s
5.first come first served scheduling
average waiting time = (0+8+(8+7)+(8+7+10)+(8+7+10+3))/5 = 15.2s
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