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Consider a preemptive priority scheduling algorithm based on dynamically changing priorities   .  Larger priority numbers imply higher priority. When a process is waiting for the CPU (in the ready queue, but not running), its priority changes at the rate A. When it is running, its priority changes at a rate B. All processes are given a priority of 0 when they enter the ready queue. The parameters A and B can be set to give many different scheduling algorithms.

a. What is the algorithm that results from B> A > 0?

b. What is the algorithm that results from A < B< 0?
in Operating System by (357 points) | 67 views
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A. As rate of change is in increasing as >0 and B>A implies that the priority is increasing with faster rate for a process in running state then process in ready state.Thus making the system behave as non-preemptive scheduling.The process whose priority is low and is in ready queue need to wait for process which is currently running.It behave like FCFS algorithm in as starting priority is same when process enter ready Queue.

B.As in this case the rate of change is decreasing with A<B implies that the new process is given chance over old process and the one entered first will be executed at the end, as rate A is decreasing at faster rate than B therefore the priority of processes in ready queue keep on decreasing.It will work like Last in first out.

Correct me if Wrong!
0
Your explanation looks appropriate. But I am a bit doubtful on the second one. Kindly elaborate it further.

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