UNIVERSITY EXAMINATIONS: 2017/2018
EXAMINATION FOR THE DIPLOMA IN BUSINESS INFORMATION
TECHNOLOGY
DBIT403 COMPUTER OPERATING SYSTEMS
DATE: AUGUST, 2018 TIME: 1 ½ HOURS
INSTRUCTIONS: Answer question One and ANY other two questions.
QUESTION ONE [30 MARKS]
(a) Explain each of the following terms as used in operating systems:- [5 Marks]
(i) Internal fragmentation
(ii) Kernel
(iii)Thread
(iv)Process Control Block (PCB)
(v) Semaphore
(b) Explain three ways in which operating systems attempt to deal with deadlocks. [3 Marks]
(c) List and explain four conditions that must hold for a deadlock condition to occur [8
Marks]
(d) Illustrate using a diagram the five state process model [7 Marks]
(e) Explain five key functions of a computer operating system [5 Marks]
(f) Differentiate between pre-emptive & non pre-emptive scheduling [2 Marks]
QUESTION TWO [20 MARKS]
(a) Highlight four file attributes [4 Marks]
(b) Explain four features of modern operating systems [4 Marks]
(c) Discuss four objectives of process scheduling [4 Marks]
(d) With the aid of diagrams, describe the following memory management techniques:-
(i) Paging [4 Marks]
(ii) Segmentation [4 Marks]
QUESTION THREE [20 MARKS]
(a) Briefly describe the following scheduling algorithms:-
(i) First-Come-First-Served (FCFS) [2 Marks]
(ii) Shortest Remaining Time (SRT) [2 Marks]
(iii)Priority Based Scheduling [2 Marks]
(b) Describe the three types of schedulers [6 Marks]
(c) Giving appropriate examples, describe the three classifications of Input/output (I/O) devices
[6 Marks ]
(d) Define the term ‘operating system’ [2 Marks]
QUESTION FOUR [20 MARKS]
(a) Define the term “ interrupt” and explain three sources of interrupts in Operating System [5
Marks]
(b) Discuss four measures that can be undertaken to ensure security of computer system
resources [8 Marks]
(c) List five operations that are associated with files [5 Marks]
(d) Give two examples of utility programs [2 Marks]
QUESTION FIVE [20 MARKS]
(a) Giving appropriate examples, describe any three types of operating systems [6 Marks]
Page 3 of 3
(b) Explain three benefits of Graphical User Interface (GUI) over Command Line Interface
(CLI) [3 Marks]
(c) Explain the functions of the following DOS commands:- [3 Marks]
(i) EXIT
(ii) MD
(iii)FORMAT
(d) Discuss four benefits of NTFS file system [4 Marks]
(e) Differentiate between the following terms:- [4 Marks]
(i) Response time & turnaround time
(ii) Multiprogramming & multiprocessing
