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Que. Consider a disk queue with request for input/output to block on cylinders

98,183,37,122,14, 124, 65, 67 in that order

Assume that disk head is  initially positioned at cylinder 53  and moving towards cylinder number 0. The total number of head movements using Shortest Seek lime First (SSTF) and SCAN algorithms are respectively
a. 236 and 252 cylinders
b. 640 and 236 cylinders
c. 235 and 640 cylinder
d. 235 and 252 cylinders
Answer:236 and 252 cylinders
kirthi :(June 18, 2018) Correct ans will be 236 and 236

SSTF: 53 to 65 then to 67 then 37 ,14,98,122,124,183
so head movement= 12+2+30+23+84+24+2+59=236

SCAN: 53 to 37 then to 14 and then to 0 (16+23+14=53) now direction will be reversed so 0 o 65 then to 67 then to 98,122,124,183 ( 65+2+31+24+2+59=183)
total head movements=183+53=236

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