B.C.A. (Semester IV) (CBCS) Examination Nov/Dec-2018
OPERTING SYSTEM
Time: 2½ Hours Max. Marks: 70
Instructions: All questions are compulsory.
Figures to the right indicate full marks.
Q.1 Choose the most correct alternatives: 14
The processes that are residing in main memory and are ready and waiting to
execute are kept on a list called
Job queue Ready queue
Execution queue Process queue
A system is in the safe state if
System can allocate resources to each process in some order still avoid a
deadlock
There exist a safe sequence
Both a at b
None of these
In FIFO page replacement algorithm, when a page must be replaced
Oldest page is chosen Newest page is chosen
Random page is chosen None of these
The main disadvantage of spinlocks is that
They are not sufficient for much process
They require busy waiting
They are unreliable sometimes
They are too complex for programmers.
Which scheduler controls the degree of multiprogramming?
Short term scheduler Long term scheduler
Middle term scheduler Pre term scheduler
Multiprogramming of computer system increases
Memory Storage
CPU utilization Cost
The page table contains
Base address of each page in physical memory
Page offset
Page size
None of these
Which of the following is contained in Process Control Block
Process Number List of open files
Memory limits All of the above
In layered architecture of computer system
Users are at the top
Operating system is in independent h/w and application program
Hardware is at the bottom
All of the above
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10) File type can be represented by
File name File extension
File identifier None of these
11) Which one of the following is a synchronization tool?
Thread Pipe
Semaphore Socket
12) In priority scheduling algorithm
CPU is allocated to the process with highest priority
CPU is allocated to the process with lowest priority
Equal priority processes cannot be scheduled
None of these
13) Process Management function of an operating system kernel includes
Process creation and termination
Process scheduling and dispatching
Process switching
All of the above
14) Which one of the following is the address generated by CPU?
Physical address Absolute address
Logical address None of these
Q.2 Answer any seven from the following. 14
Define fragmentation.
Define Race Condition.
Define Best fit.
Define Real Time Systems. Give examples of Real Time Application.
What is contiguous memory allocation?
What are the operations on process?
What are the various operations on a file?
What is LRU page replacement?
Define Structure of Operating system.
Q.3 Answer any two from the followings:- 10
List out the different components of system. Explain any two in detail.
Draw discuss the state diagram of a process in detail.
What is a resource allocation graph? Explain with example.
Explain critical section problem with example? 04
Q.4 Answer any two from the followings:- 14
Consider the following reference string given below:
2
How many page faults will occur for the following page replacement? Consider
the memory is empty initially and memory has 3 frames.
FIFO page replacement algorithm
ii) Optimal page replacement algorithm
What is Semaphore? Explain its properties along with drawbacks.
Which are the necessary conditions for Deadlock? Explain Deadlock recovery
in brief.
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Q.5 Answer any two from the followings:- 14
Consider the following set of processes, with the length of CPU- burst time
given in milliseconds and priority of the process (consider 1 as highest priority):
Process Arrival time Burst time Priority
P1 0 10 3
P2 1 17 1
P3 3 3 3
P4 4 7 4
P5 5 12 2
Solve the following questions:
Draw the 3 Gantt chart illustrating the execution of these process using
SJF, priority and Round Robin (Quantum 5).
What is average waiting time for each process and average turnaround time
in each scheduling algorithm?
Define following terms:
Throughput
Waiting Time
Turnaround Time
Response Time
CPU Utilization
File
Demand paging
What is Paging? Explain paging mechanism in MMU with example.