Assignment

Question One

Disk requests come into the disk driver for cylinders: 86, 1470, 913, 1774, 948, 1509, 1022, 1750, 130 in that order. The disk has 5000 total cylinders (numbered 0 to 4999) and the disk head positioned over cylinder 143 and previous request was at cylinder 125. What is the sequence of reads and calculate the total distance the read/write head will traverse using Shortest Seek Time First and SCAN algorithms?

Question Two

(a) What are the short comings of shortest seek time first (SSTF) disk scheduling algorithm?
(b) What is a bootstrap program, and where is it stored?

Question Three

Explain the concept of a bus and daisy chain. Indicate how they are related.

Question Four

What you think is it better that we put the functionality in the device controller instead of kernel? Give reason of your answer.