Basic Electrical Engineering
Previous Year 2019-2020


OPERATING SYSTEMS
BRANCH : CSE
Max Marks : 100
Time : 3 Hours
Q.CODE : HRB457
Answer Question No.1 (Part-1) which is compulsory, any EIGHT from Part-II and any TWO
from Part-III.
The figures in the right hand margin indicate marks.
Part- I

Q1 Only Short Answer Type Questions (Answer All-10) (2 x 10)
a) What is the main purpose of an operating system?

Ans:


b) To access the services of operating system, the interface is provided by the
.
c) Define Dispatcher, dispatch latency.
d) How many types of fragmentation occur in Operating System? How they can
overcome?
e) The bounded buffer problem is also known as _
.
f) Which facility dynamically adds probes to a running system, both in user processes
and in the kernel?
g) Specify the benefits of multithreaded programming?
h) Differentiate between mutex and semaphore.
i) Enlist the different RAID levels.
j) Define Belady’s Anomaly.
Part- II
Q2 Only Focused-Short Answer Type Questions- (Answer Any Eight out of Twelve) (6 x 8)
a) What is the main advantage of the layered approach to system design? Explain with
diagram.
b) Design the structure of process control block.
c) Define system calls. Describe about the different operations done by several system
calls.
d) Which are the necessary conditions to achieve a deadlock?
e) Given a memory partition having hole of 100k, 500k, 200k, 300k, 600k in order. How
process of 212k,417k, 112k, 420k. Can be fit into those holes in order by using
4 partition selection algorithm.
f) Consider Logical Address Space is 256mb, Physical Address is 25 bits, offset field
contains 13 bits. Find out page size, no of frames, no of pages.
g) State and explain Banker’s algorithm.
h) Explain paging technique with TLB. Find out the hit ratio required to reduce the
effective memory access time of 200 ns without TLB to 140 ns with TLB. Assume TLB
access time is 25 ns.
i) Write short answer on: Linux system, VM ware.
j) Enlist the various File Access methods.
k) Suppose main memory has 3 frames & page nos which are going to be referenced are
5,0,3,9,4,7,6,0,1,0,4. Then find out total page fault & page hit.
l) Explain cycle stealing method and IPC mechanism.