Scheduling Algorithm

You will calculate the total distance that a disk arm moves to satisfy pending requests, for different disk scheduling algorithms.

Steps

1. Suppose that a disk drive has 5,000 cylinders, numbered 0 to 4,999. The drive is currently serving a request at cylinder 143, and the previous request was at cylinder 125. The queue of pending requests, in first-in-first-out (FIFO) order, is as follows:

92; 1,320; 879; 1,984; 1,023; 1,690; 1,123; 2,002; and 93

2. Calculate the total distance in cylinders—starting from the current head position—that the disk arm moves to satisfy all the pending requests, for each of the following disk scheduling algorithms:

FCFS
SSTF
SCAN
LOOK
C-SCAN