Question

         Process                    Arrival Time                             Burst Time

                        P1                                0                                              2

                        P2                                1                                              1

                        P3                                2                                              4

                        P4                                3                                              2

                        P5                                4                                              1

Consider a set of processes given above with the arrival time and the length of CPU burst time given in cycles. Show a Gantt chart and calculations of average turnaround time and average waiting time of these processes under the shortest job first (SJF) with preemption CPU scheduling algorithm and the round-robin scheduling algorithm with a time quantum of 1 cycle. (10 points)

Answer 1

1.

Shortest Job First (SJF) Preemptive - SJF Preemptive is a scheduling technique in which the job with the shortest remaining burst time is executed at any time among the available process. Whenever the CPU receives a job with a burst time of less than the remaining burst time of current executing process, the current executing process is removed from execution and replaced by that job with the shortest remaining burst time.

2.

Round Robin - Round Robin is a preemptive scheduling technique in which each process gets the execution queue for a particular time slice and then is replaced by the next process. This process of cyclic execution continues till all the process are executed.