UGC NET · PAPER 2
UGC NET Paper 2 Computer Science – Unit 5: System Software and Operating System PYQ (June 2024 Re-Exam)
Q5. Which of the following statements are TRUE about mutual exclusion in concurrent programming?
(A) Mutual exclusion ensures that only one process can be in a critical section at any given time.
(B) Mutual exclusion is designed to prevent conflicts and ensure that only one process can access shared resources at a time.
(C) Mutual exclusion can use various algorithms to ensure that processes do not enter the critical section simultaneously.
(D) Mutual exclusion allows multiple processes to access the critical section simultaneously to improve performance.
Choose the correct answer from the options given below:
(A) Mutual exclusion ensures that only one process can be in a critical section at any given time.
(B) Mutual exclusion is designed to prevent conflicts and ensure that only one process can access shared resources at a time.
(C) Mutual exclusion can use various algorithms to ensure that processes do not enter the critical section simultaneously.
(D) Mutual exclusion allows multiple processes to access the critical section simultaneously to improve performance.
Choose the correct answer from the options given below:
- (A), (B), (C) Only
- (B), (C), (D) Only
- (B), (D), (A) Only
- (A), (C), (D) Only
Q16. Which of the following statements are TRUE about privileged instructions?
(A) They can only be executed by the operating system kernel and not by user applications.
(B) They are designed to perform operations that can directly affect the hardware or system state, such as I/O operations or changing memory-management settings.
(C) User applications can execute privileged instructions if they have the correct permissions set by the operating system.
(D) They are usually executed in user mode to ensure the safety and security of the system.
Choose the correct answer from the options given below:
(A) They can only be executed by the operating system kernel and not by user applications.
(B) They are designed to perform operations that can directly affect the hardware or system state, such as I/O operations or changing memory-management settings.
(C) User applications can execute privileged instructions if they have the correct permissions set by the operating system.
(D) They are usually executed in user mode to ensure the safety and security of the system.
Choose the correct answer from the options given below:
- (A) and (B) Only
- (A), (B) and (C) Only
- (B) and (C) Only
- (B), (C) and (D) Only
Q55. Match List I (Algorithms) with List II (Characteristics)
| List I | List II |
|---|---|
| (A) First Come First Served (FCFS) | (I) Each process is assigned a priority. |
| (B) Shortest Job First (SJF) | (II) Ensures fair allocation of CPU time by assigning a time slice. |
| (C) Round Robin (RR) | (III) Processes are executed in the order they arrive. |
| (D) Priority Scheduling | (IV) Selects the process with the smallest next burst time. |
- (A)-(II), (B)-(III), (C)-(IV), (D)-(I)
- (A)-(II), (B)-(IV), (C)-(III), (D)-(I)
- (A)-(III), (B)-(IV), (C)-(II), (D)-(I)
- (A)-(III), (B)-(IV), (C)-(I), (D)-(II)
Q57. Match List I (operating system concepts) with List II (characteristics)
| List I | List II |
|---|---|
| (A) Paging | (I) Evicts least recently used page |
| (B) LRU (Least Recently Used) | (II) Extends physical memory |
| (C) C-SCAN | (III) Logical to physical mapping |
| (D) Virtual Memory | (IV) Circular disk access |
- (A)-(III), (B)-(IV), (C)-(I), (D)-(II)
- (A)-(III), (B)-(I), (C)-(IV), (D)-(II)
- (A)-(I), (B)-(III), (C)-(IV), (D)-(II)
- (A)-(I), (B)-(IV), (C)-(III), (D)-(II)
Q75. Which of the following statements are TRUE about the Process Control Block (PCB)?
(A) The PCB contains information about the process state, such as whether it is running, waiting or terminated.
(B) The PCB includes the program code and data segments of the process.
(C) The PCB stores the process's memory-management information, such as page tables and segment tables.
(D) The PCB is used to track process scheduling information and CPU registers for process execution.
Choose the correct answer from the options given below:
(A) The PCB contains information about the process state, such as whether it is running, waiting or terminated.
(B) The PCB includes the program code and data segments of the process.
(C) The PCB stores the process's memory-management information, such as page tables and segment tables.
(D) The PCB is used to track process scheduling information and CPU registers for process execution.
Choose the correct answer from the options given below:
- (A), (B) and (C) Only
- (B), (C) and (D) Only
- (A), (C) and (D) Only
- (A) and (B) Only
Directions (Q96–100): The Banker's Algorithm is a deadlock-avoidance method in operating systems, designed to facilitate resource allocation without causing deadlock. It maintains information about the maximum resources each process may require, the currently allocated resources and the available resources in the system. The algorithm checks each resource request to determine whether granting it would leave the system in a safe state, meaning that there is always a sequence in which all processes can complete their execution without getting stuck due to resource unavailability. Each process must specify its maximum demand for each resource type before it starts execution. When a process requests additional resources, the algorithm checks if granting the request will keep the system in a safe state. If so, the resources are allocated; otherwise the process must wait until its request can be safely fulfilled.
Q96. Which of the following is NOT a requirement for the Banker's algorithm to grant a resource request?
- The requested resources must be available.
- The system must be in a safe state after granting the request.
- The request must not exceed the maximum resources the process can request.
- The process must be the only one requesting resources.
Q97. Which data structures does the Banker's Algorithm use to maintain the state of available, maximum and allocated resources?
- Priority Queue
- Hash table
- Wait-for Graph
- Matrices and Vectors
Q98. What is the significance of the Banker's algorithm in terms of resource management?
- It ensures that all processes can finish their execution without deadlock.
- It eliminates the need for processes to request resources.
- It accelerates the execution of critical sections in processes.
- It minimizes the number of context switches between processes.
Q99. What is the primary goal of the Banker's Algorithm?
- To allocate resources optimally
- To prevent processes from requesting resources
- To detect and recover from deadlocks
- To maximise CPU utilization
Q100. What information is used to determine if a resource request can be granted?
- Available resources and current allocation of each process
- CPU utilization of each process
- Number of processes waiting for resources
- Arrival time of each process