Consider the following set of processes,with the arrival times and the CPU-burst times for the processes P0,P1 and P2.
The pre-emptive shortest job first scheduling algorithm is used.Scheduling is carried out only at arrival or completion of processes. What is the average waiting time for the three process?
a. 5.0 ms b. 4.33ms c. 6.33 ms d. 7.33 ms
waiting time = compilation time - arrival time - burst time
average waiting time= total waiting time/total no. of process
create gantt chart
0 2 5 13 22
waiting time(P0) = 13-0-9 = 4
waiting time(P1) = 5-1-4 = 0
waiting time(P2) = 22-2-9 =11
average waiting time = 15 /3
=5, ans is a.