A disk having 200 tracks (0-199). The request sequence(82,170,43,140,24,16,190) are shown in the given figure and the head position is at 50.
(a)736
(b)314
(c)123
(d)520
ANSWER:
Question 2
Consider a disk queue with requests for I/O to blocks on cylinders 98, 183, 41, 122, 14, 124, 65, 67. The LOOK scheduling algorithm is used. The head is initially at cylinder number 53 moving towards larger cylinder numbers on its servicing pass. The cylinders are numbered from 0 to 199. The total head movement (in number of cylinders) incurred while servicing these requests is _______.
(a)299
(b)250
(c)851
(d)169
ANSWER:
Question 3
Request sequence = {176, 79, 34, 60, 92, 11, 41, 114}
Initial head position = 50
Direction = right (We are moving from left to right)
(a)450
(b)420
(c)630
(d)291
ANSWER:
Question 4
Consider the following disk request sequence for a disk with 100 tracks
98, 137, 122, 183, 14, 133, 65, 78
Head pointer starting at 54 and moving in left direction. Find the number of head movements in cylinders using LOOK scheduling.
(a)220
(b)209
(c)429
(d)301
ANSWER:
Question 5
Q.93, 176, 42, 148, 27, 14, 180 is the request queue. Head pointer is at 55. Calculate seek time using LOOK.
