Priority scheduling is a non-preemptive algorithm and one of the most common scheduling algorithms in batch systems. Each process is assigned a priority. Process with the highest priority is to be executed first and so on.
Processes with the same priority are executed on first come first served basis. Priority can be decided based on memory requirements, time requirements or any other resource requirement.
1- First input the processes with their burst time and priority. 2- Sort the processes, burst time and priority according to the priority. 3- Now simply apply FCFS algorithm.
Note: A major problem with priority scheduling is indefinite blocking or starvation. A solution to the problem of indefinite blockage of the low-priority process is aging. Aging is a technique of gradually increasing the priority of processes that wait in the system for a long period of time.
Order in which processes gets executed 1 3 2 Processes Burst time Waiting time Turn around time 1 10 0 10 3 8 10 18 2 5 18 23 Average waiting time = 9.33333 Average turn around time = 17
In this post, the processes with arrival time 0 are discussed. In next set, we will be considering different arrival times to evaluate waiting times.
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Improved By : SHUBHAMSINGH10