homework 4

Deadline: Day 22/04/2018 @ 23:59

[Total Mark for this Assignment is 4]

Operating Systems

IT241

College of Computing and Informatics

Question One

1 Marks

Learning Outcome(s): 1

Describe the OS mechanism for process management, timing, memory, I/O, file and concurrency management.

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

1 Marks

Learning Outcome(s): 1

Describe the OS mechanism for process management, timing, memory, I/O, file and concurrency management.

(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

1 Mark

Learning Outcome(s):

Describe the OS mechanism for process management, timing, memory, I/O, file and concurrency management.

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

Question Four

1 Mark

Learning Outcome(s):

Describe the OS mechanism for process management, timing, memory, I/O, file and concurrency management.

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