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F.C.F.S
Theory :
  FCFS (First-Come-First-Serve) is the easiest disk scheduling algorithm among all the scheduling algorithms. In the FCFS disk scheduling algorithm, each input/output request is served in the order in which the requests arrive. In this algorithm, starvation does not occur because FCFS address each request.




Advantages:

  • In FCFS disk scheduling, there is no indefinite delay.
  • There is no starvation in FCFS disk scheduling because each request gets a fair chance.

Disadvantages:

  • FCFS scheduling is not offered as the best service.
  • In FCFS, scheduling disk time is not optimized.

Example:

The following chart shows the sequence in which requested tracks are serviced using C-LOOK.


Therefore, the total seek count is calculated as: = (176-50)+(176-79)+(79-34)+(60-34)+(92-60)+(92-11)+(41-11)+(114-41) = 510

Steps to excute:

  • Input the queue you want to be scheduled using FCFS.
  • Input the current position of the head.
  • After execution of the queue you will get the required seek count and the seek sequence.
Output of the algorithm