BCA-07/DCA-102
June Examination 2017
BCA Pt. II/DCA Examination
Operating System I
Paper BCA-07/DCA-102
Time 3 Hours Max. Marks 100
Note: The question paper is divided into three sections B and C. Write answers as per given instructions.
Section A 10 × 2 20
(Very Short Answer Questions)
Note: Answer all questions. Limit to 30 words. All carries 2 marks.
What is Kernel?
What do you mean by Batch Processing?
Define the essential properties of Real time operating system.
State dining philosopher's problem.
What is the "degree of multiprogramming"?
Name an algorithm for deadlock avoidance.
What is polling?
(viii) What is safe state (with respect to deadlock)?
426
BCA-07/DCA-102 200 3 (P.T.O.)
BCA-07/DCA-102 200 3 (Contd.)
426
When does page fault occurs?
State Belady's anomaly.
Section B 4 × 10 40
(Short Answer Questions)
Note: Answer any four questions. Each answer should not
exceed 200 words. Each question carries 10 marks.
What is an operating system? What are the services offered
by the operating system?
Explain system call. How does it differ from function call.
What is race condition? Explain critical section problem. How
are semaphores used for solving critical section problem?
Differentiate user-level threads and Kernel level threads.
What is the deadlock? What are the necessary conditions to
occur the deadlock? What are the various methods to recover
from the deadlock?
Write short note on file access control.
What is the need of security in OS? Explain any three program
and system threads to OS.
Compute number of page fault for LRU and FIFO and optimal
page replacement algorithms. The given page trace is
7 (12 pages). The job is allowed 3 blocks
in primary memory.
BCA-07/DCA-102 200 3
426
Section C 2 × 20 40
(Long Answer Questions)
Note: Answer any two questions. Limit your answer to 500
words. All carries 20 marks each.
10) Explain the architecture of operating system. Differentiate
process and program. Also describe PCB and its contents.
11) What is Socket? Illustrate the working of Remote Procedure
call.
12) Discuss the need of scheduler in OS. Consider the following
set of process with the arrival time and CPU burst time given
in milliseconds.
Process Arrival time CPU burst time
P1 0 8
P2 1 4
P3 2 9
P4 3 5
What is average waiting time for processes with preemptive
shortest job first scheduling?
13) Explain various memory allocation scheme first fit, next fit,
worst fit. What do you understand by memory fragmentation?