Suppose that a disk drive has 1,024 cylinders, numbered 0 to 1,023. The driver is currently serving a request at cylinder 257 and has previously serviced cylinder 156. The queue of pending requests is as follows: 94 145 715 487 655 1005 630 753 905 Starting from the current head position, what is the total distance traversed by the disk arm in satisfying all the requests using the ff. disk scheduling algorithm: FCFS, SSTF, SCAN,C-SCAN, LOOK and C-LOOK. Use chart to illustrate the head movement per algorithm.

Suppose that a disk drive has 1,024 cylinders, numbered 0 to 1,023. The driver is currently serving a request at cylinder 257 and has previously serviced cylinder 156. The queue of pending requests is as follows: 94 145 715 487 655 1005 630 753 905 Starting from the current head position, what is the total distance traversed by the disk arm in satisfying all the requests using the ff. disk scheduling algorithm: FCFS, SSTF, SCAN,C-SCAN, LOOK and C-LOOK. Use chart to illustrate the head movement per algorithm.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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