Practice IT Operating System Questions and Answers

• A system uses demand paging with an average page fault service time of 10 milliseconds and a memory access time of 100 nanoseconds. If the desired effectiv...
• Which of the following is a potential problem when multiple threads access and modify shared data concurrently without proper synchronization?
• A process is currently in the "Running" state. If its allocated time slice expires, to which state will it typically transition?
• Consider three processes P1, P2, and P3 with burst times 10ms, 10ms, and 10ms respectively. If they arrive at time 0 and are scheduled using FCFS (First-Co...
• What is the primary function of the Program Counter (PC) in a CPU?
• Which of the following is NOT one of the four necessary conditions for a deadlock to occur?
• A semaphore is initialized to 1. If two processes P1 and P2 both try to execute a `wait()` (P) operation on this semaphore, what is the maximum number of p...
• A system uses paging with a logical address space of 2^26 bytes and a page size of 4 KB. How many bits are required for the page number in the logical addr...
• Which memory management technique divides the logical address space into fixed-size blocks and the physical memory into frames of the same size?
• What is the phenomenon where a process spends more time paging (swapping pages between main memory and disk) than executing instructions?
• Which of the following is NOT a primary function of an operating system?
• A system call is typically implemented as a(n):
• Which of the following process states represents a process waiting for an I/O operation to complete?
• In multithreading programming, what is a critical section?
• Which CPU scheduling algorithm gives preference to processes with shorter CPU burst times?
• Deadlock can arise if four necessary conditions hold simultaneously. Which of the following is NOT one of them?
• Which memory management technique divides logical memory into blocks of the same size, called pages, and physical memory into blocks of the same size, call...
• A system uses a 32-bit logical address space and a page size of 4KB. If each page table entry (PTE) is 4 bytes, how many entries can a single-level page ta...
• Consider three processes P1, P2, P3 with burst times 10, 5, 8 milliseconds respectively. All arrive at time 0. If they are scheduled using the Shortest Job...
• Which of the following is a primary reason for using threads instead of multiple processes for concurrent execution within a single application?
•  A deadlock situation can be completely prevented if which of the following conditions is eliminated?
• Which system call is typically used by a parent process to wait for a child process to terminate?
• In the context of file systems, what is the primary purpose of an inode?
• Consider a delete_node(head, key) function for a singly linked list that removes the first occurrence of a node with a given key. The function works for mo...
• A custom stack implementation has a pop() method that is supposed to remove and return the top element. However, when the stack is empty, calling pop() cau...
• A recursive function calculate_height(node) is designed to find the height of a binary tree (where a single node has height 0). The function is implemented...
• An insert(root, value) function for a Binary Search Tree (BST) is implemented recursively. After inserting several elements, a search(root, value) function...
• A hash map (or dictionary) implemented with separate chaining is exhibiting very poor performance, even with a seemingly good hash function. Operations lik...
• A function sum_matrix_elements(matrix, R, C) is designed to sum all elements of a matrix with R rows and C columns. The implementation uses nested loops: t...
• Consider the array arr = [1, 2, 3, 4, 5] and the following operations: 1.  arr.insert(2, 9) (inserts 9 at index 2) 2.  arr.pop(3) (removes element at ind...
• Consider a singly linked list: 1 -> 2 -> 3 -> 4 -> None. If a delete_node(head, 3) function is called (which deletes the node with value 3), what will be t...
• A queue initially empty undergoes the following sequence of operations: 1.  enqueue(10) 2.  enqueue(20) 3.  dequeue() 4.  enqueue(30) 5.  dequeue() 6....
• Consider the Quick Sort algorithm with the last element as the pivot. For the array [7, 2, 1, 6, 8, 5, 3, 4], what will be the state of the array *after th...
• Given the array [38, 27, 43, 3, 9, 82, 10], what would be the two sorted subarrays immediately *before the final merge step* in a Merge Sort algorithm?
• Perform a dry run of Binary Search for target = 29 in the sorted array [2, 12, 15, 17, 27, 29, 45]. What are the values of mid in each iteration until the ...
• Consider a graph with vertices A, B, C, D and edges with weights: (A,B)=1, (A,C)=7, (A,D)=10, (B,C)=3, (C,D)=4, (D,E)=2. (Assume E is another vertex). If y...
• Given a set of activities with start and finish times: (1,4), (3,5), (0,6), (5,7), (3,9), (5,9), (6,10), (8,11), (8,12), (2,14), (12,16). If you apply the ...
• Using a bottom-up dynamic programming approach to calculate the 6th Fibonacci number (F(0)=0, F(1)=1), what are the values stored in the DP table F at indi...
• For matrix dimensions p = {10, 20, 30, 40}, representing matrices A (10x20), B (20x30), C (30x40). What is the minimum number of scalar multiplications req...
• Consider generating all permutations of the string "ABC" using a backtracking approach. Which of the following sequences represents a valid path in the rec...