Quiznetik

Operating System (OS) | Set 3

1. The FCFS algorithm is particularly troublesome for

Correct : B. multiprogramming systems

2. What is ‘Aging’?

Correct : D. increasing the priority of jobs to ensure termination in a finite time

3. An SJF algorithm is simply a priority algorithm where the priority is

Correct : A. the predicted next cpu burst

4. Which of the following scheduling algorithms gives minimum average waiting time?

Correct : B. sjf

5. What is an operating system?

Correct : D. all of the mentioned

6. To access the services of operating system, the interface is provided by the

Correct : A. system calls

7. Which one of the following is not true?

Correct : C. kernel is made of various modules which can not be loaded in running operating system

8. Which one of the following error will be handle by the operating system?

Correct : D. all of the mentioned

9. What is the main function of the command interpreter?

Correct : A. to get and execute the next user-specified command

10. In Operating Systems, which of the following is/are CPU scheduling algorithms?

Correct : D. all of the mentioned

11. If a process fails, most operating system write the error information to a

Correct : A. log file

12. Which facility dynamically adds probes to a running system, both in user processes and in the kernel?

Correct : A. dtrace

13. Which one of the following is not a real time operating system?

Correct : D. palm os

14. The OS X has

Correct : B. hybrid kernel

15. The systems which allow only one process execution at a time, are called

Correct : B. uniprocessing systems

16. In operating system, each process has its own

Correct : D. all of the mentioned

17. In Unix, Which system call creates the new process?

Correct : A. fork

18. What is interprocess communication?

Correct : B. communication between two process

19. Which system call can be used by a parent process to determine the termination of child process?

Correct : A. wait

20. The address of the next instruction to be executed by the current process is provided by the

Correct : B. program counter

21. The number of processes completed per unit time is known as

Correct : B. throughput

22. Which of the following is not the state of a process?

Correct : B. old

23. What is a Process Control Block?

Correct : B. data structure

24. The entry of all the PCBs of the current processes is in

Correct : C. process table

25. What is the degree of multiprogramming?

Correct : D. the number of processes in memory

26. A single thread of control allows the process to perform

Correct : A. only one task at a time

27. What is the objective of multiprogramming?

Correct : C. to increase cpu utilization

28. Which of the following do not belong to queues for processes?

Correct : B. pcb queue

29. When the process issues an I/O request

Correct : A. it is placed in an i/o queue

30. What will happen when a process terminates?

Correct : A. it is removed from all queues

31. What is a long-term scheduler?

Correct : A. it selects processes which have to be brought into the ready queue

32. If all processes I/O bound, the ready queue will almost always be              and the Short term Scheduler will have a              to do.

Correct : C. empty, little

33. What is a medium-term scheduler?

Correct : C. it selects which process to remove from memory by swapping

34. What is a short-term scheduler?

Correct : B. it selects which process has to be executed next and allocates cpu

35. The primary distinction between the short term scheduler and the long term scheduler is

Correct : C. the frequency of their execution

36. In a multiprogramming environment

Correct : C. more than one process resides in the memory

37. The context of a process in the PCB of a process does not contain

Correct : D. context switch time

38. Which of the following need not necessarily be saved on a context switch between processes?

Correct : B. translation lookaside buffer

39. Which of the following does not interrupt a running process?

Correct : C. scheduler process

40. Which process can be affected by other processes executing in the system?

Correct : A. cooperating process

41. When several processes access the same data concurrently and the outcome of the execution depends on the particular order in which the access takes place, is called?

Correct : B. race condition

42. If a process is executing in its critical section, then no other processes can be executing in their critical section. This condition is called?

Correct : A. mutual exclusion

43. Which one of the following is a synchronization tool?

Correct : C. semaphore

44. A semaphore is a shared integer variable

Correct : A. that can not drop below zero

45. Mutual exclusion can be provided by the

Correct : C. both mutex locks and binary semaphores

46. When high priority task is indirectly preempted by medium priority task effectively inverting the relative priority of the two tasks, the scenario is called

Correct : A. priority inversion

47. Process synchronization can be done on

Correct : C. both hardware and software level

48. A monitor is a module that encapsulates

Correct : D. all of the mentioned

49. To enable a process to wait within the monitor

Correct : A. a condition variable must be declared as condition

50. Restricting the child process to a subset of the parent’s resources prevents any process from

Correct : C. overloading the system by creating a lot of sub-processes

51. A parent process calling            system call will be suspended until children processes terminate.

Correct : A. wait

52. Cascading termination refers to termination of all child processes before the parent terminates

Correct : A. normally

53. In UNIX, each process is identified by its

Correct : C. process identifier

54. The child process can

Correct : A. be a duplicate of the parent process

55. The child process completes execution, but the parent keeps executing, then the child process is known as

Correct : B. zombie

56. What is Inter process communication?

Correct : B. allows processes to communicate and synchronize their actions without using the same address space

57. Message passing system allows processes to

Correct : A. communicate with one another without resorting to shared data

58. Which of the following two operations are provided by the IPC facility?

Correct : D. receive & send message

59. Messages sent by a process

Correct : C. can be fixed or variable sized

60. The link between two processes P and Q to send and receive messages is called

Correct : A. communication link

61. Which of the following are TRUE for direct communication?

Correct : B. a communication link can be associated with exactly two processes

62. In indirect communication between

Correct : C. there is a mailbox to help communication between p and q

63. In the non blocking send

Correct : B. the sending process sends the message and resumes operation

64. In the Zero capacity queue

Correct : B. the sender blocks until the receiver receives the message

65. The Zero Capacity queue

Correct : B. is referred to as a message system with no buffering

66. Concurrent access to shared data may result in

Correct : C. data inconsistency

67. A situation where several processes access and manipulate the same data concurrently and the outcome of the execution depends on the particular order in which access takes place is called

Correct : B. race condition

68. The segment of code in which the process may change common variables, update tables, write into files is known as

Correct : B. critical section

69. Which of the following conditions must be satisfied to solve the critical section problem?

Correct : D. all of the mentioned

70. Mutual exclusion implies that

Correct : A. if a process is executing in its critical section, then no other process must be executing in their critical sections

71. Bounded waiting implies that there exists a bound on the number of times a process is allowed to enter its critical section

Correct : A. after a process has made a request to enter its critical section and before the request is granted

72. A minimum of            variable(s) is/are required to be shared between processes to solve the critical section problem.

Correct : B. two

73. In the bakery algorithm to solve the critical section problem

Correct : B. each process receives a number (may or may not be unique) and the one with the lowest number is served next

74. An un-interruptible unit is known as

Correct : B. atomic

75. TestAndSet instruction is executed

Correct : C. atomically

76. Semaphore is a/an                to solve the critical section problem.

Correct : C. integer variable

77. What are the two atomic operations permissible on semaphores?

Correct : A. wait

78. What are Spinlocks?

Correct : D. all of the mentioned

79. What is the main disadvantage of spinlocks?

Correct : B. they require busy waiting

80. The wait operation of the semaphore basically works on the basic                system call.

Correct : B. block()

81. The signal operation of the semaphore basically works on the basic                system call.

Correct : B. wakeup()

82. If the semaphore value is negative

Correct : A. its magnitude is the number of processes waiting on that semaphore

83. The code that changes the value of the semaphore is

Correct : C. critical section code

84. What will happen if a non-recursive mutex is locked more than once?

Correct : B. deadlock

85. What is a semaphore?

Correct : C. can be accessed from multiple processes

86. What are the two kinds of semaphores?

Correct : B. binary & counting

87. What is a mutex?

Correct : B. must be accessed from only one process

88. A binary semaphore is a semaphore with integer values

Correct : A. 1

89. Semaphores are mostly used to implement

Correct : B. ipc mechanisms

90. The bounded buffer problem is also known as

Correct : C. producer – consumer problem

91. In the bounded buffer problem, there are the empty and full semaphores that

Correct : A. count the number of empty and full buffers

92. To ensure difficulties do not arise in the readers – writers problem                are given exclusive access to the shared object.

Correct : B. writers

93. The dining – philosophers problem will occur in case of

Correct : A. 5 philosophers and 5 chopsticks

94. A deadlock free solution to the dining philosophers problem

Correct : B. does not necessarily eliminate the possibility of starvation

95. A monitor is a type of

Correct : C. high level synchronization construct

96. A monitor is characterized by

Correct : A. a set of programmer defined operators

97. A procedure defined within a                   can access only those variables declared locally within the                and its formal parameters.

Correct : D. monitor, monitor

98. If no process is suspended, the signal operation

Correct : C. nothing happens

99. A collection of instructions that performs a single logical function is called

Correct : A. only one process can be active at a time within the monitor

100. What are the operations that can be invoked on a condition variable?

Correct : A. wait & signal