1
GATE CSE 2023
MCQ (Single Correct Answer)
+2
-0.67

Consider the two functions incr and decr shown below.


incr() {
  wait(s);
  X = X+1;
  signal(s);
}

decr() {
   wait(s);
   X = X-1;
   signal(s);
}

There are 5 threads each invoking incr once, and 3 threads each invoking decr once, on the same shared variable X. The initial value of X is 10.

Suppose there are two implementations of the semaphore s, as follows:

I-1: s is a binary semaphore initialized to 1.

I-2: s is a counting semaphore initialized to 2.

Let V1, V2 be the values of X at the end of execution of all the threads with implementations I-1, I-2, respectively.

Which one of the following choices corresponds to the minimum possible values of V1, V2, respectively?

A
15, 7
B
7, 7
C
12, 7
D
12, 8
2
GATE CSE 2023
Numerical
+2
-0

Consider the following two-dimensional array D in the C programming language, which is stored in row-major order:

int D[128] [128];

Demand paging is used for allocating memory and each physical page frame holds 512 elements of the array D. The Least Recently Used (LRU)( page-replacement policy is used by the operating system. A total of 30 physical page frames are allocated to a process which executes the following code snippet:

for (int i = 0; i < 128; i++)

$$\quad$$ for (int j = 0; j < 128; j++)

$$\quad\quad$$D[j] [i] *= 10;

The number of page faults generated during the execution of this code snippet is _____________.

Your input ____
3
GATE CSE 2023
Numerical
+2
-0

Consider a computer system with 57-bit virtual addressing using multi-level tree-structured page tables with L levels for virtual to physical address translation. The page size is 4 KB (1 KB = 1024 B) and a page table entry at any of the levels occupies 8 bytes.

The value of L is ____________.

Your input ____
4
GATE CSE 2023
Numerical
+1
-0

The integer value printed by the ANSI-C program given below is ___________.


#include<stdio.h>
int funcp(){
    static int x = 1;
    x++ ;
    return x;
}
int main(){
    int x,y;
    x = funcp();
    y = funcp()+x;
    printf("%d\n", (x+y));
    return 0;
}
Your input ____
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