SHORTEST JOB FIRST
S.J.F.
Basic Theory :
Shortest Job First (SJF) is an algorithm in which the process
having the smallest execution time is chosen for the next
execution.
It is non-preemptive algorithm. It significantly reduces the average waiting time for other processes awaiting execution. This scheduling algorithm is optimal if all the jobs/processes are available at the same time (either Arrival time is 0 for all, or Arrival time is same for all). In SJF scheduling, the process with the lowest burst time, among the list of available processes in the ready queue, is going to be scheduled next.
It is non-preemptive algorithm. It significantly reduces the average waiting time for other processes awaiting execution. This scheduling algorithm is optimal if all the jobs/processes are available at the same time (either Arrival time is 0 for all, or Arrival time is same for all). In SJF scheduling, the process with the lowest burst time, among the list of available processes in the ready queue, is going to be scheduled next.
- Sort all the process according to the arrival time.
- Then select that process which has minimum arrival time and minimum Burst time.
- After completion of process make a pool of process which after till the completion of previous process and select that process among the pool which is having minimum Burst time.