M.Sc. (Semester (CBCS) Examination Mar/Apr-2018
Computer Science
OPERATING SYSTEM
Time: 2½ Hours
Max. Marks: 70
Instructions: Question No. 1 and 2 are compulsory. Attempt any 3 questions from Q. no. 3 to Q. no. 7 Figures to the right indicate full marks.
Q.1

Choose correct alternatives.
10
Page making process from main memory to disk is called
Interruption
Termination
Swapping
None of the above
Remote computing service involves the use of time sharing and
Multiprocessing
Interactive processing
Batch processing
Socket
Which scheduling policy is most suitable for time shared operating system?
SJF
FCFS
Round-robin
All of the above
of the distributed file system are dispersed among various machines of distributed system.
Client
Server
Storage devices
All of the above
Bankers algorithm is used for purpose.
Deadlock avoidance
Deadlock removal
Deadlock prevention
All of the above
By using the specific system call, we can
Open the file
Read the file
Write into file
All of the above.
The principle of locality of reference justifies the use of
Virtual memory
Interrupts
Cache memory
Secondary memory
Which one of the following is not a valid state of a thread
Running
Parsing
Ready
All of the above
synchronizes critical resources to prevent deadlock.
p-operator
v-operator
Semaphore
swapping
10) Variable partition memory management technique with compaction results in
Reduction in fragmentation
Minimal usage
Segment
All of the above
Page 2 of 2
SLR-UG-270

State following statements are True or False.
04
Thrashing implies excessive page I/O.
Fragmentation is dividing the main memory into equal size fragments.
Page fault is an error in specific page.
Fork is the creation of new process.
Q.2

Write short notes on the following.
08
Mutual exclusion.
Segmentation.

Answer the following.
06
Explain various states of process.
What is thread? Explain in details.
Q.3
Answer the following.
14

What is a system call? Explain the various types of system call provided by operating system.

What is semaphore? Discuss producer-consumer problem with semaphore.
Q.4
Answer the following.
14

Briefly explain about single level, two level and tree structured directories.

Discuss various methods for the prevention of deadlock.
Q.5
Answer the following.
14

Explain in detail indexed file allocation method.

What is paging? Discuss paging model of logical and physical memory.
Q.6
Answer the following.
14

Explain and compare the FCFS and SJF disk scheduling algorithms.

What are the methods of free space management of disk?
Q.7
Answer the following.
14

What is the meaning of the terms access right and domain.

Explain advantages and disadvantages of distributed systems over centralized system.