Self Studies

Operating Syste...

TIME LEFT -
  • Question 1
    2 / -0.33

    The main function of the dispatcher (the portion of the process scheduler) is:

  • Question 2
    2 / -0.33

    Consider the following set of processes {A, B, C, D}, with the arrival time and the CPU burst time given in milliseconds.

    Process Id

    Arrival time

    Burst time

    A

    4

    3

    B

    9

    1

    C

    0

    4

    D

    8

    5

     

    What is the average waiting time in millisecond for these processes with the shortest job first algorithm? 

  • Question 3
    2 / -0.33

    Suppose there is a paging system with a translation lookaside buffer. Assuming that the entire page table and all the pages are in the physical memory, what is the effective memory access time in ms if it takes 5 msec to search the TLB and 70 msec to access physical memory? The TLB hit ratio is 0.8.

  • Question 4
    2 / -0.33

    Consider a computer system having R resources of the same type and these resources are shared by 6 processes that have maximum demands of 7, 5, 3, 8, 4, 6 respectively. Then for what minimum values of R, the system will not be in deadlock?

  • Question 5
    2 / -0.33

    Which of the following is TRUE about user-level threads and kernel-level threads?

    S1: Typically if a user-level thread is performing blocking system call then the entire process will be blocked

    S2: Kernel level threads are designed as dependent threads

    S3: Every thread has its own register and stack

  • Question 6
    2 / -0.33

    Consider a hypothetical system with byte-addressable memory, 64-bit logical addresses, 8 Megabyte page size and page table entries of 16 bytes each. What is the size of the page table in the system in terabytes?

  • Question 7
    2 / -0.33

    Suppose that jobs arrive according to the following schedule :                                                 

    Process Arrival time    Run time
    A12
    37
    62
    D85
    E92
    F1212

       

    Now give the sequence of the processes as they gets share of CPU if the scheduler used is Shortest Remaining Time First.

  • Question 8
    2 / -0.33

    The process executes the code where x is an integer and x is initialized to 10

    while(--x){

    fork();

    if(x == 2)

    break;

    }

    The total number of child processes created is

  • Question 9
    2 / -0.33

    A system has 12 identical resources and Y processes competing for them. Each process can request at most 3 resources. Which one of the following values of Y could lead to a deadlock?

  • Question 10
    2 / -0.33

    At time 0, an OS with round-robin scheduling (time quantum = 5 units) has 5 processes P1, P2, P3, P4, P5 with burst times 15, 10, 20, 5, 15 respectively. What is the average turn-around time?

  • Question 11
    2 / -0.33

    Which of the following is/are not true about the deadlock scheme?

    I.  In deadlock avoidance, number the resource uniquely and never requests a lower-numbered resource

    II. In deadlock avoidance, the request for the resources is always granted if the resulting state is safe.

    III. In deadlock prevention, never request a resource after releasing any resource.

  • Question 12
    2 / -0.33

    Consider a counting semaphore S. The operation P(S) performs the operation S = S – 1 and operation V(S) performs the operation V = V + 1. During program execution, 13P and 5V operation is performed in the some order. Find the number of processes in a blocked state with initial counting semaphore value 1.

  • Question 13
    2 / -0.33

    A computer uses 48 bits Virtual Address Space, 256 GB of physical memory with page size of 4 KB. The page table size is 4 bytes and if each entry fits in a single page the number of levels of paging required is _____.

  • Question 14
    2 / -0.33

    Consider two processes P1 and P2 executing their respective codes initial values of global variables P1_inside and P2_inside are “false”.

    P1

    P2

    while(true)

    {

    while(P1_inside);

    P1 inside=true;

    C.S.                  // critical section

    P1 inside =false;

    }

    while(true)

    {

    while(P2_inside);

    P2 inside=true;

    C.S.                    // critical section

    P2 inside=false;

    }

     

    Consider the below statements:

    1. Mutual exclusion is satisfied
    2. Mutual Exclusion is not satisfied
    3. It is possible for deadlock

    Which of the above are true?

  • Question 15
    2 / -0.33

     

    Allocation

    Max

    Available

     

    A     B      C     D

    A     B      C    D

    A     B      C       D

    P0

      0     0      1        2

    0     0      1        2

    1     5      2        0

    P1

    1     0       0       0

    1     7      5        0

     

    P2

    1     3      5        4

      2     3      5        6  

     

    P3

    0     6      3         2

    0     6      5        2

     

    P4

    0     0       1          4

    0     6      5        6

     

    Which of the following is true for the above-given resource allocation table?

  • Question 16
    2 / -0.33

    Consider a file system that uses inodes to represent files. Disk blocks are 12 KB in size, and a pointer to a disk block requires 8 bytes. This file system has 10 direct disk blocks, as well as single and double indirect disk blocks. What is the maximum size in GB (up to two decimals) of a file that can be stored in this file system?

  • Question 17
    2 / -0.33

    Consider a n-way set associative cache memory with 8 sets and 16 cache blocks (0-15) and a main memory with 512 blocks (0 - 511). What memory blocks will be present in the cache after the sequence 17, 4, 13, 105, 28, 29, 200, 408, 127, 205, 411, 251 if LRU is used as a cache replacement block?

  • Question 18
    2 / -0.33

    Three CPU-bound tasks, with execution times of 15, 12 and 5 time units respectively arrive at times 0, t and 8, respectively. If the operating system implements a shortest remaining time first scheduling algorithm, what should be the value of t to have 4 context switches?

    Ignore the context switches at time 0 and at the end.

Submit Test
Self Studies
User
Question Analysis
  • Answered - 0

  • Unanswered - 18

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
Submit Test
Self Studies Get latest Exam Updates
& Study Material Alerts!
No, Thanks
Self Studies
Click on Allow to receive notifications
Allow Notification
Self Studies
Self Studies Self Studies
To enable notifications follow this 2 steps:
  • First Click on Secure Icon Self Studies
  • Second click on the toggle icon
Allow Notification
Get latest Exam Updates & FREE Study Material Alerts!
Self Studies ×
Open Now