Manipal University 2009 B.E Communication Engineering Opertating Systems - Question Paper

1 a) What is an operating system? "An operating system as a resource allocator" justify
your answer?
b) discuss the virtual machine system model along with its benefits?
c) define the differences ranging from among short-term and log-term Scheduling?
(3 + four + 3)
2 a) what is a thread? discuss the benefits of multithreaded programming?
b) Consider the subsequent set of processes with a length of the CPU burst time provided in
milliseconds.
Process
Arrival Time
Burst Time
Priority
P1
0
7
3
P2
3
2
2
P3
4
3
1
P4
4
1
1
P5
5
3
3
Instructions to Candidates
• ans ANY 5 ques..
MANIPAL INSTITUTE OF TECHNOLOGY
(Constituent Institute of MANIPAL University) MANIPAL-576104
Draw Charts illustrating the execution of these processes using SRTF and
Preemptive Priority. obtain out which of them provides outcomes in the minimal avg.
turnaround time and waiting time. Show all the steps.
c) What is meant by race condition of concurrent access? discuss with an example?
(3 + four + 3)
3 a) explain the issues with the semaphore? provide the solution to the Dining-Philosophers
issue using Monitors?
b) What is a resource allocation graph? explain the problems related with recovery from
deadlock?
Page one of 2
c) provided a system with total resources of A(3); B(14); and C(12), and the subsequent
snapshot : compute the need matrix and check the system for deadlock using Banker's
algorithm. Show all the steps.
Process Allocation Maximum Available A B C A B C A B C
P0 0 0 one 0 0 one 1 five 2
P1 one 0 0 one seven 5
P2 one three five two three 5
P3 0 six three 0 six 5
P4 0 0 one 0 six 5
(3 + three + 4)
4 a) With the help of a diagram discuss the hardware support needed for paging. What is
the effective access time of paged memory?
b) discuss the segmented memory management with an example?
c) Consider the page reference stream 1, 2, 3, 4, 2, 1, 5, 6, 2, 1, 2, 3, 7, 6, 3, 2, 1, 2, 3, 6.
How many page faults would occur for FIFO and LRU algorithms, assuming four frames?
obtain out which 1 of the most efficient. Show all the steps. (3 + three + 4)
5 a) What is a file? elaborate the various kinds of file types? provide their functions with an
example for each?
b) Suppose the head of moving disk with 200 tracks numbered 0-199. Suppose the current
request being serviced is for track 50 and the previous request serviced was for track 45.
Queue = 50, 45, 180, 35, 150, 5, 145, 51, 54.
What is the total number of head movements needed to satisfy these requests using the
SSTF algorithm and also show the head movement. Show all the steps.
c) What is principle of lowest privilege and need to know? discuss the protection using
access matrix with an example? (3 + four +3 )
6 a) What is an intruder and cracker? Differentiate ranging from VIRUS and WORM?
b) define the levels of security measures for to protect a system?
c) discuss the synchronization in Linux? (4 + three + three )
Page

Reg No.

MANIPAL INSTITUTE OF TECHNOLOGY (Constituent Institute of MANIPAL University)

MANIPAL-576104

FIFTH SEMESTER B.E.(CSE) MAKEUP EXAMINATION-JAN 2009

OPERATING SYSTEMS AND UNIX (CSE-307) (10 POINT CREDIT SYSTEM)

TIME DURATION: 3 HOUR

Instructions to Candidates

Answer ANY FIVE questions.

1    a) What is an operating system? An operating system as a resource allocator justify

your answer?

b)    Explain the virtual machine system model along with its benefits?

c)    Describe the differences between among short-term and log-term Scheduling?

(3 + 4 + 3)

2    a) what is a thread? Explain the benefits of multithreaded programming?

b) Consider the following set of processes with a length of the CPU burst time given in milliseconds.

Process	Arrival Time	Burst Time	Priority
P1	0	7	3
P2	3	2	2
P3	4	3	1
P4	4	1	1
P5	5	3	3

Draw Charts illustrating the execution of these processes using SRTF and Preemptive Priority. Find out which of them provides results in the minimal average turnaround time and waiting time. Show all the steps.

c) What is meant by race condition of concurrent access? Explain with an example?

(3 + 4 + 3)

3 a) Discuss the problems with the semaphore? Give the solution to the Dining-Philosophers problem using Monitors?

b) What is a resource allocation graph? Discuss the issues related with recovery from deadlock?

c) Given a system with total resources of A(3); B(14); and C(12), and the following snapshot : calculate the need matrix and check the system for deadlock using Bankers

algorithm. Show all the steps.

Process Allocation Maximum Available A B C A B C A B C P0 0 0 1 0 0 1 1 5 2 P1 1 0 0 1 7 5 P2 1 3 5 2 3 5 P3 0 6 3 0 6 5 P4 0 0 1 0 6 5

(3 + 3 + 4)

4    a) With the help of a diagram explain the hardware support required for paging. What is

the effective access time of paged memory?

b)    Explain the segmented memory management with an example?

c)    Consider the page reference stream 1, 2, 3, 4, 2, 1, 5, 6, 2, 1, 2, 3, 7, 6, 3, 2, 1, 2, 3, 6. How many page faults would occur for FIFO and LRU algorithms, assuming 4 frames? Find out which one of the most efficient. Show all the steps.    (3 + 3 + 4)

5    a) What is a file? What are the different types of file types? Give their functions with an

example for each?

b)    Suppose the head of moving disk with 200 tracks numbered 0-199. Suppose the current request being serviced is for track 50 and the previous request serviced was for track 45. Queue = 50, 45, 180, 35, 150, 5, 145, 51, 54.

What is the total number of head movements needed to satisfy these requests using the SSTF algorithm and also show the head movement. Show all the steps.

c)    What is principle of least privilege and need to know? Explain the protection using access matrix with an example?    (3 + 4 +3 )

6    a) What is an intruder and cracker? Differentiate between VIRUS and WORM?

b)    Describe the levels of security measures for to protect a system?

c)    Explain the synchronization in Linux?    (4 + 3 + 3 )

Page 2 of 2

Attachment: manipal-university-2009-b-e-communication-engineering-3354-1.pdf

Earning:   Approval pending.