c program for sjf non preemptive scheduling

printf ( ' p%d %d %d %d' ,p ,bt ,wt ,tat ).

//turnaround time of individual processes.

printf ( ' Process Burst Time Waiting Time Turnaround Time' ).

//individual WT by adding BT of all previous completed processes.

//finding the waiting time of all the processes.

printf ( 'Enter number of process:' ).

int bt ,p ,wt ,tat ,i ,j ,n ,total = 0 ,totalT = 0 ,pos ,temp.

* C Program to Implement SJF Scheduling.

So that's how the procedure will go on in shortest job first (SJF) scheduling algorithm. Till then we have three more processes arrived in the ready queue hence the scheduler will choose the process with the lowest burst time.Īmong the processes given in the table, P3 will be executed next since it is having the lowest burst time among all the available processes. This will be executed till 8 units of time. Till now, we have only one process in the ready queue hence the scheduler will schedule this to the processor no matter what is its burst time. Since, No Process arrives at time 0 hence there will be an empty slot in the Gantt chart from time 0 to 1 (the time at which the first process arrives).Īccording to the algorithm, the OS schedules the process which is having the lowest burst time among the available processes in the ready queue. Their arrival time and burst time are given in the table below. In the following example, there are five jobs named as P1, P2, P3, P4 and P5. There are different techniques available by which, the CPU burst time of the process can be determined.

It is not implementable because the exact Burst time for a process can't be known in advance.May suffer with the problem of starvation.Minimum average waiting and turnaround time.However, it is very difficult to predict the burst time needed for a process hence this algorithm is very difficult to implement in the system. 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. However, SJF scheduling algorithm, schedules the processes according to their burst time. Till now, we were scheduling the processes according to their arrival time (in FCFS scheduling). Next → ← prev Shortest Job First (SJF) Scheduling

C program for sjf non preemptive scheduling