Disk Scheduling (45 Points). Assume that you are trying to schedule track requests for the arm on a disk with 150 tracks. Currently the following set of disk requests exists in a queue (order that requests were received): 66, 138, 93, 77, 79, 24, 5. The disk arm can move at the rate of 1 track per time unit. As these requests are being processed, four more requests come in at the following times: 111 at t=20, 14 at t=50, 102 at t=75, and 22 at t=100. Using the simulation format and scheduling policies we covered in class, complete the following the problems: Assuming that the disk arm is currently positioned over track 49, use the Shortest Seek Time First (SSFT) Scheduler to indicate the order in which the track requests are processed, and the total amount of time that it takes to process the entire set.
Assuming that the disk arm is currently positioned over track 49 and is traveling in the direction of increasing track numbers, use the Circular Scan (C-SCAN) Scheduler to indicate the order in which the track requests are processed, and the total amount of time that it takes to process the entire set. Assume that the quick return from the end of the disk to the beginning takes 5 time units.
Assuming that the disk arm is currently positioned over track 49 and is traveling in the direction of increasing track numbers, use the LOOK Scheduler to indicate the order in which the track requests are processed, and the total amount of time that it takes to process the entire set.