Operating System BSCIT 2nd question

Sikkim Manipal University of Health, Medical and Technological Sciences
(University Center: College for Professional Studies, Center Code: 1537)
PRE-FINAL EXAMINATION, DEC. 2008
Bachelors of Science in Information Technology (BScIT)

Subject: Operating System Code: BT 0036
Time: 1.5 Hrs Max Marks: 100
Semester: II Min Marks: 50
INSTRUCTIONS

1. Write all the information like roll no., name of the student, class, semester, subject name, subject code, etc. on the answer paper and also the roll no on the question paper.
2. This paper is divided into four sections A, B, C and D.
3. Section A, B, and C consists of multiple choice questions of 1, 2 and 4 marks respectively and section D contains subjective type questions.
4. Write all the answers on the answer sheets provided and do not write anything on the question paper.
5. Do not fold, bend, cut, tear, staple, punch, tie or otherwise deface/mutilate the answersheet in any manner.
6. Read the questions carefully and attempt the questions accordingly.



PART A (1X20=20)

1. When the job requests printer to output a line, that line is copied to the system buffer and is written to disk. After the job is complete the output is printed. This form of processing is called
(a) job scheduling (b) I/O device scheduling
(c) spooling (d) multiprogramming


2. ………….operating system allows many users to share the computer simultaneously.
(a) batch processing
(b) multiprogramming
(c) real time
(d) parallel


3. ………..is an example of asymmetric multiprogramming.
(a) Mac OS 7
(b) Mutimax
(c) Soraris 2
(d) Sun OS Version 4

4. ………….model has the benefit of running many processes at once.
(a) IBM 1560
(b) Mutimax
(c) Encore’s nix
(d) Windows NT

5. The delay between job submission and job completion time is called ………………….
(a) Turnaround time
(b) Throughput
(c) Seek time
(d) Execution time

6. The process is waiting for some event occur is known as ………………………..
(a) Newborn process
(b) Waiting state
(c) Ready state
(d) Running state

7. In parallel system, the ability to continue providing service to proportional to the level of surviving hardware is called ………….
(a) fault tolerant
(b) graceful degradation
(c) both (a) and (b)
(d) none of the above

8. An operating system is a program that acts as intermediate between
(a) a user and software
(b) a user of computer and hardware
(c) hardware and humanware
(d) liveware and firmware

9. Physical memory is broken into fixed sized blocks called ……………..
(a) Frame (b) Pages
(c) Page Table (d) Page Map

10. In the direct communication there are……….
(a) more than two links associated with the processes
(b) a link is associated with exactly two processes
(c) either one or more
(d) none of the above

11. ………provides a mechanism to allow processes to communicate and synchronize their actions.
(a) Inter process communication
(b) Buffering technique
(c) Scheduler
(d) Process control block

12. Paging system is used to avoid the …….. problem
(a) Internal fragmentation
(b) External fragmentation
(c) Fragmentation
(d) None of the above

13. What is the meaning of MAX in Banker’s Algorithm data structure?
(a) maximum demand of each process
(b) available resources of each type
(c) currently allocated to each process
(d) remaining resources need of each process

14. The ……………scheduler selects processes from this pool and loads them into memory for execution
(a) simple-term
(b) mid-term
(c) long-term
(d) short-term

15. A logical address is a collection of ……in segmentation.
(a) frame
(b) segments
(c) faults
(d) offsets

16. An address generated by the CPU is commonly referred as………….
(a) logical address
(b) physical address
(c) memory address
(d) all of the above

17. Multiprogramming refers to:
(a) having several programs in RAM at the same time
(b) Multitasking
(c) Writing programs in multiple languages
(d) None of the above

18. ………..directory structures allow subdirectories and files to be shared.
(a) acylic-graph
(b) general graph
(c) tree-structured
(d) single-level

19. The zero capacity buffers have a ………..
(a) maximum length 0
(b) potentially infinite length
(c) finite length of N
(d) none of the above

20. Multilevel feedback queue allows processes to move from ………
(a) one queue to another
(b) one process to another
(c) process to queue
(d) all of the above

PART B (2X10=20)

21. Short-term scheduler executes at least once every ………………………..
(a) 1 milliseconds
(b) 10 milliseconds
(c) 100 milliseconds
(d) 1000 milliseconds

22. When a process creates a new process, two possibilities exist in terms of execution.
1. The parent continues to execute concurrently with its children.
2. The parent waits until some or all of its children have terminated.
3. The child process duplicates and exits.
4. The child process follows the parent process.

(a) 1, 4 (b) 2, 3
(c) 1, 2 (d) 1, 3

23. Interprocess communication establishes the link logically for send receive operations. Identify the properties of direct line communication.
1. A link is associated with exactly two processes.
2. A link may be associated with more than two processes.
3. Between each pair of processes, there exists exactly one link.
4. The link may be unidirectional or bidirectional.
5. The link may be unidirectional, but usually bidirectional.

(a) 1, 2, 3, 4, 5 (b) 1, 3, 5
(c) 2, 3, 4 (d) 3, 4, 5

24. Context switch means………………….
(i) Saving the state of old process, loading the saved state for the new process.
(ii) Saving the state of new process, loading the saved state for old process.
(iii) Saving the state of new process, loading old process state for the new process.
(iv) Saving the state of old process state, loading the new process state.

(a) i, ii (b) ii, iii
(c) i (d) All

25. In a batch system there are more processes submitted than can be………………….
(a) executed in dqueue
(b) executed in circular queue
(c) executed immediately
(d) none of the above

26. Every address generated by the CPU is divided into two parts. They are:
(a) page number and offset
(b) Page table and fault
(c) Index table and frame
(d) Offset address and index address

27. A time sharing operating system ………………
(a) Allows the single user to share the computer simultaneously.
(b) Allows many users to share the computer simultaneously
(c) Allows many users not to share the computer simultaneously
(d) Allows many users to share resources simultaneously

28. …………technique used for the total program size my be large, the portion that is actually used may be much smaller.
(a) Dynamic loading
(b) Dynamic Binding
(c) Address Binding
(d) (a) and (b)

29. A relocation register is ……………
(a) Base register
(b) Logical register
(c) Physical register
(d) All of the above

30. Physical memory is broken into fixed-sized blocks called ………and logical memory is also broken into blocks of the same size called ……..
(a) Pages and Frames
(b) Fragments and Pages
(c) Fragmentation and Frames
(d) Frames and Pages

PART C (4X8=32)

31. A PCB contains many information. An empty block tier is shown at the right and the PCB shown on the list. Match them.






1. Process number (i)
2. Register (ii)
3. Pointer (iii)
4. Memory limit (iv)
5. List of open files (v)
6. Program counter (vi)

(a) 1-i, 2-ii, 3-iii, 4-iv, 5 –v, 6 – vi
(b) 1-2, 2-iv, 3-i, 4-v, 5-vi, 6 – iii
(c) 1-iv, 2-iii, 3-v, 4-ii, 5-I, 6-vi
(d) 1-vi, 2-v, 3-iv, 4-1, 5-ii, 6-iii

32. Given the process resource graph, find the two minimal cycles.


















(a) P1  R1  P2  R3  P2  R2
P2  R3  P3  R2
(b) P1  R1  P2  R3  P3  R2  P1
P2  R3  P3  R2  P2
(c) P1  R1  P2  R2  P1  P2  R3  P3  R2
(d) P1  R2  P2  R2
R3  P3  R2  P2

33. Termination housekeeping means…………
(i) A process in a critical section terminates either voluntarily or involuntarily and it must release mutual exclusion so that other processes may enter their critical section.
(ii) A process in a critical section begins voluntarily and it must release mutual exclusion so that other process may enter critical section.
(iii) A process in critical section terminates involuntarily and it must release mutual exclusion so that other processes may enter their critical section.
(iv) A process in critical section terminates voluntarily and it must release mutual exclusion so that other processes may enter their critical section.

(a) i, ii (b) ii, iii
(c) i only (d) None

34. Decker’s algorithm is he ………….
(a) software solution to the mutual exclusion
(b) hardware solution to the mutual exclusion
(c) software solution to the un-mutual exclusion
(d) software solution to the producer, consumer relationship

35. The number of faults occurred when FIFO page replacement algorithm was used for a given string set 7, 0, 1, 2, 0, 3, 0, 4, 2, 3, 0, 3, 2, 1, 2, 1, 70, 1 is
(a) 10
(b) 9
(c) 15
(d) 12

36. Given the set of input processes and their burst requirement what is the average waiting time if SJF algorithm is used for CPU scheduling?

Process Burst
P1 6
P2 8
P3 7
P4 3

(a) 7 (b) 9
(c) 15 (d) 24.5

37. It is a phenomenon in virtual memory schemes when the processor spends most of its time swapping pages, rather than executing instructions. This is due to an inordinate number of page faults called ………….
(a) Context switch
(b) Belady’s anomaly
(c) Thrashing
(d) All of the above

38. How can a semaphore s be used to sole the critical-section problem?
(a) Initialize s to 0; enter section after waiting on s; exit after signaling on s.
(b) Initialize s to 1; enter section after waiting on s; exit after signaling on s.
(c) Initialize s to 0; enter section after signaling on s; exit after waiting on s.
(d) Initialize s to 1; enter section after signaling on s; exit after waiting on s.

PART D (7X4=28)
Attempt any four questions.
1. Explain the different states of process.
2. What are the necessary conditions for deadlock to occur?
3. What is FIFO page replacement algorithm?
4. Write short note on: (a) Spooling and (b) Thrashing
5. Write down the characteristics of distributed systems and timesharing systems.
6. What is priority scheduling? Illustrate with an example.


BEST OF LUCK