Consider a disk queue with requests for 1/O to blocks on cylinders 82,170,43,140,24,16,190 The head is initially at cylinder number 50. The cylinders are numbered from 0 to 199. Calculate the total number of head movements needed to satisfy these requests for the following disk scheduling algorithms 1. FCFS 2. SSTF 3. SCAN(moving towards larger cylinder numbers on its servicing pass) 4. C-SCAN 5 C-LOOK

Consider a disk queue with requests for 1/O to blocks on cylinders 82,170,43,140,24,16,190 The head is initially at cylinder number 50. The cylinders are numbered from 0 to 199. Calculate the total number of head movements needed to satisfy these requests for the following disk scheduling algorithms 1. FCFS 2. SSTF 3. SCAN(moving towards larger cylinder numbers on its servicing pass) 4. C-SCAN 5 C-LOOK

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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