The 4999 in SCAN and C-SCAN signifies that the disc head has to be shifted to track 4999, the last track.
The total number of cylinders traversed and the sequence in which the tracks are accessible are shown in the following table.
Total:
SSTF: 2150 2069 2296 2800 3681 4965 1618 1523 1212 544 356 7586. FCFS :2150 2069 1212 2296 2800 544 1618 356 1523 4965 3681 13011.
SCAN :2150 2296 2800 3681 4965 4999 2069 1618 1523 1212 544 356 7492.
LOOK: 2150 2296 2800 3681 4965 2069 1618 1523 1212 544 356 7424 C-SCAN 2150 2296 2800 3681 4965 4999 0 356 544 1212 1523 1618 2069 9917
C-LOOK: 2150 2296 2800 3681 4965 356 544 1212 1523 1618 2069 9137.
Storage System Operating Systems Homework 3 Solutions - Spring 2019 2 In
The 4999 in SCAN and C-SCAN signifies that the disc head has to be shifted to track 4999, the last track. The disc head only scans in one direction with the C-SCAN. Because of this, when the desk heads have finished with track 4999, they must return to track 0 and scan in the same direction.
The complete question is suppose that a disk drive has 5,000 cylinders, numbered 0 to 4,999. the drive is currently serving a request at cylinder 2,150, and the previous request was at cylinder 1,805. the queue of pending requests, in fifo order, is: 2069, 1212, 2296, 2800, 544, 1618, 356, 1523, 4965, 3681 starting from the current head position, what is the total distance (in cylinders) that the disk arm moves to satisfy all the pending requests for each of the following disk-scheduling algorithms?
(a) First-Come-First-Serve (FCFS)
(b) Shortest-Seek-Time-First (SSTF)
(c) SCAN
(d) C-SCAN
(e) LOOK
(f) C-LOOK
To learn more about C SCAN refer to:
https://brainly.com/question/15318640
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