Suppose that a disk drive has 200 cylinders, numbered 0 to 199. The drive is currently servicing request at cylinder 60 and the previous request was at cylinder 80. The queue has a pending request at cylinder 58, 26, 54, 68, 49, 61, 63, 69 ,24, 14 and 90. Starting from the current head position, what is the total distance (in cylinders) that the disk arm moves to satisfy all the pending requests by using the Shortest Seek Time First algorithm.

Suppose that a disk drive has 200 cylinders, numbered 0 to 199. The drive is currently servicing request at cylinder 60 and the previous request was at cylinder 80. The queue has a pending request at cylinder 58, 26, 54, 68, 49, 61, 63, 69 ,24, 14 and 90. Starting from the current head position, what is the total distance (in cylinders) that the disk arm moves to satisfy all the pending requests by using the Shortest Seek Time First algorithm.

Operations Research : Applications and Algorithms

4th Edition

ISBN:9780534380588

Author:Wayne L. Winston

Publisher:Wayne L. Winston

Chapter20: Queuing Theory

Section20.10: Exponential Queues In Series And Open Queuing Networks

Problem 10P

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