Operating Systems207810 marksNumerical: disk scheduling algorithmsDisk scheduling algorithms
Suppose that a disk has 100 cylinders, numbered 0 to 99. The drive is currently serving a request at cylinder 45. The queue of pending request, in FIFO order is: 88, 72, 13, 74, 48, 9, 22, 50, 35 and 30. What is the total distance (in cylinders) that the disk arm moves to satisfy all pending request
Suppose that a disk has 100 cylinders, numbered 0 to 99. The drive is currently serving a request at cylinder 45. The queue of pending request, in FIFO order is: 88, 72, 13, 74, 48, 9, 22, 50, 35 and 30. What is the total distance (in cylinders) that the disk arm moves to satisfy all pending request for each of the following disk scheduling algorithms? a) FCFS b) SCAN c) SSTF[10]
- Total cylinders: 0 to 99 (100 cylinders) - Current head position: 45 - FIFO request queue: 88, 72, 13, 74, 48, 9, 22, 50, 35, 30 --- Serve in FIFO order: $45 \to 88 \to 72 \to 13 \to 74 \to 48 \to 9 \to 22 \to 50 \to 35 \to 30$ Move Distance ---------------- 45→88 43 88→72 16 72→13 59 13→74 61 ...