A disk head is initially positioned at track 32. The disk I/O request queue, in arrival order, is: 98, 37, 14, 124, 65, 67. Using the FCFS disk-scheduling algorithm, find the total number of head movements (in tracks) required to service all requests.
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Correct answer: C. 321
Explanation
FCFS services requests strictly in their arrival order, without any reordering by proximity. Starting at track 32: |98−32|=66, |37−98|=61, |14−37|=23, |124−14|=110, |65−124|=59, |67−65|=2. Summing these: 66+61+23+110+59+2 = 321 total track movements, option (iii).More Database Management Systems questions
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