Download JNTUH MCA 3rd Sem R15 2017 August 823AA Operating Systems Question Paper

Download JNTUH (Jawaharlal nehru technological university) MCA (Master of Computer Applications) 3rd Sem (Third Semester) Regulation-R15 2017 August 823AA Operating Systems Previous Question Paper

R15

Code No: 823AA















JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

MCA III Semester Examinations, August - 2017

OPERATING SYSTEMS

Time: 3hrs













Max.Marks:75


Note: This question paper contains two parts A and B.


Part A is compulsory which carries 25 marks. Answer all questions in Part A.



Part B consists of 5 Units. Answer any one full question from each unit. Each



question carries 10 marks and may have a, b, c as sub questions.



PART - A



















5 ? 5 Marks = 25


1.a) What are system programs?













[5]

b) Distinguish between a process and a thread.









[5]

c) What are inverted page tables?













[5]

d) Explain different file access methods.











[5]

e) Explain how resource allocation graph is constructed.







[5]



PART - B

















5 ? 10 Marks = 50


2.

What are time shared and real time systems? Explain them in detail.



[10]

OR

3.a)

What are operating system objectives and functions?

b)

What are virtual machines? What is their significance?







[5+5]


4.

What is critical section problem? Discuss the various hardware solutions to critical
section problem.

















[10]

OR

5.

Explain real time scheduling using an example.









[10]


6.

Explain various LRU-Approximation page replacement algorithms.



[10]

OR

7.

What is thrashing? Why does it occur? What are different methods to handle thrashing.

























[10]



8.

Define file. Discuss various file allocation strategies. Discuss the merits and demerits of
various file allocation strategies.













[10]

OR

9.

What are the merits and demerits of tree structured directories and acyclic graph directory
structure?



















[10]










10.

Consider the following snapshot of a system:

Allocation max available
A B C D A B C D A B C D
P0 0 0 1 2 0 0 1 2 1 5 2 0
P1 1 0 0 0 1 7 5 0
P2 1 3 5 4 2 3 5 6
P3 0 6 3 2 0 6 5 2
P4 0 0 1 4 0 6 5 6
Answer following questions using banker's algorithm:

a) What is the content of the matrix need?
b) Is the system in a safe state?
c) If a request from a process p1 arrives for (0,4,2,0) can the request be granted
immediately?

















[10]

OR

11.

What is a deadlock? Discuss various deadlock prevention strategies.



[10]



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