Question 3853 – Operating-Systems

A disk drive has 100 cyclinders, numbered 0 to 99. Disk requests come to the disk driver for cyclinders 12, 26, 24, 4, 42, 8 and 50 in that order. The driver is currently serving a request at cyclinder 24. A seek takes 6 msec per cyclinder moved. How much seek time is needed for shortest seek time first (SSTF) algorithm?

Correct Answer: D

Step-1:

Step-2: Total seek time= 420 msec.
Step-3: =420/1000
=0.42
Note: 1000 msec = 1 sec