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

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 12P

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