UNIVERSITY EXAMINATIONS: 2014/2015
EXAMINATION FOR THE DIPLOMA IN INFORMATION TECHNOLOGY
DIT 30I DBIT 403 OPERATING SYSTEMS
DATE: AUGUST 2016 TIME: 1½HOURS
INSTRUCTIONS: Answer Any THREE Questions.
QUESTION ONE
a) Differentiate between layered and monolithic operating system structures. (2 Marks)
b) Define the following terms (4 Marks)
i. Context Switching
ii. Process state
c) Differentiate between Pre-emptive and Non-preemptive scheduling. (4 Marks)
d) Explain briefly any two conditions for a deadlock in Operating Systems. (4 Marks)
e) Explain the following terms: (2 Marks)
i. Process
ii. Thread
QUESTION TWO
a) Discuss any three methods of managing security in operating systems. (6 Marks)
b) State and describe any I/O scheduling algorithms. (10 Marks)
c) State any two advantages of UNIX based operating systems over windows based operating
system. (4 Marks)
QUESTION THREE
a) With the aid of a diagram describe the paging process. (5 Marks)
b) Describe the objectives of memory management. (10 Marks)
c) Explain the five process states using a diagram. (5 Marks)
QUESTION FOUR
a) List three factors to consider in selecting an operating system. (3 Marks)
b) Explain two sources of interrupts. (4 Marks)
c) Explain three forms of explicit inter-process interaction. (6 Marks)
d) Describe four advantages of threads over processes. (4 Marks)
e) State and explain 3 basic function of input and output management (3 Marks)
QUESTION FIVE
a) How can deadlock be prevented in a system and what is the philosophy of deadlock
prevention? (4 Marks)
b) What is a control structure that the operating system uses to keep the information of the
process context? Give the pieces of information that are likely to be in this structure.
(4 Marks)
c) Clearly explain the compaction process in the main memory. (4 Marks)
d) Discuss how fragmentation manifest itself in each of the following type of virtual storage
(6 Marks)
i. Segmentation
ii. Paging
iii. Combined paging/segmentation.
e) Define the term deadlock as used in Operating Systems (2 Marks)
