UNIVERSITY EXAMINATIONS: 2017/2018
EXAMINATION FOR THE DIPLOMA IN BUSINESS INFORMATION
TECHNOLOGY
DIT301 DBIT301: OPERATING SYSTEMS
DATE: NOVEMBER, 2017 TIME: 1 ½ HOURS
INSTRUCTIONS: Answer Question ONE and any other TWO questions.
QUESTION ONE (30 MARKS)
(a) What is the difference between pre-emptive scheduling and non-pre-emptive scheduling?
(2Marks)
(b) Explain the following computer software categories and two examples of each
(i) Operating System. (3 Marks)
(ii) Utility programs. (3 Marks)
b) Describe FOUR file management activities supported by an operating system. (4 Marks)
c) With the aid of diagrams, describe the following memory management techniques: –
(i) Swapping (4 Marks)
(ii) Multiple partition allocation. (4 Marks)
d) Explain the term ‘operating system’. (2 Marks)
e) Explain FOUR operating systems types. (8 Marks)
QUESTION TWO (20 MARKS)
a) Explain any six functions of the operating system. (6 Marks)
b) List and explain the functions of the three types of schedulers. (9 Marks)
c) Computer systems face threats which are both logical and physical in nature. Explain
how a system can be physically secured. (5 Marks)
QUESTION THREE (20 MARKS)
(a) What is a process scheduler? Explain THREE characteristics of a good process scheduler.
(4 Marks)
b) Allan wants to buy operating system software for his network system. Outline six factors
that he would consider when buying the software . (6 Marks)
c) State four objectives of the Input/output device manager. (4 Marks)
d) Describe the following process scheduling techniques: – (6 Marks)
(i) FIFO
(ii) Priority scheduling
(iii) Shortest Job first
QUESTION FOUR (20 MARKS)
a) Define the following terms as used in computers. (4 Marks)
i) Kernel
ii) Application Software
iii) Internal fragmentation
iv) Computer
b) Explain the three ways of handling deadlocks. (6 Marks)
c) Outline four causes of computer interrupts. (4 Marks)
d) Explain FOUR components of PCB. (4 Marks)
e) Outline four benefits of GUI over Command Driven Interfaces. (2 Marks)
QUESTION FIVE (20 MARKS)
a) Using a well labelled process state model, explain the five states of a process.
(7Marks)
b) Outline five objectives of process scheduling. (5 Marks)
c) List and explain four conditions necessary for a deadlock to occur. (8 Marks)