Assume that a disk can perform a seek to an adjacent cylinder in 1 millisecond and a full-stroke seek over all 5000 cylinders in 18 milliseconds. The total seek times for FCFS is computed to be 65.20, SSTF is 31.52, SCAN is 62.02, LOOK is 40.29, C-SCAN is 62.10 and C-LOOK is 40.42. Which of the algorithms is the fastest? And what is the percentage speedup of the fastest algorithm over FCFS?

Assume that a disk can perform a seek to an adjacent cylinder in 1 millisecond and a full-stroke seek over all 5000 cylinders in 18 milliseconds. The total seek times for FCFS is computed to be 65.20, SSTF is 31.52, SCAN is 62.02, LOOK is 40.29, C-SCAN is 62.10 and C-LOOK is 40.42. Which of the algorithms is the fastest? And what is the percentage speedup of the fastest algorithm over FCFS?

Systems Architecture

7th Edition

ISBN:9781305080195

Author:Stephen D. Burd

Publisher:Stephen D. Burd

Chapter12: Secondary Storage Management

Section: Chapter Questions

Problem 12VE

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