A disk has 300 cylinders (0 to 299). The read-write head is at cylinder 101, moving towards the higher end. Calculate the total head movement with the C-LOOK policy for the requests 123, 45, 197, 87, 250, 198, 280.
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Correct answer: A. 456
Explanation
Going up: 123, 197, 198, 250, 280 (280 − 101 = 179). Jump back to 45 (280 − 45 = 235), then to 87 (42). Total = 179 + 235 + 42 = 456.More System Software and Operating System questions
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