Operating System MCQs with Answers
Practice important Operating System MCQs with answers and explanations.
Chapter: 17
Q441:
What is the average queue length for the SJF scheduling algorithm as computed using Little's formula?
A. 1.8
B. 2.3
C. 3
D. 1.5
Correct Answer:
A
Chapter: 17
Q442:
The 'nice' value in UNIX scheduling helps to prevent a user from migrating out of its assigned __________.
A. Kernel Group
B. User Group
C. I/O group
D. Process queue
Correct Answer:
A
Chapter: 17
Q443:
Scheduling algorithms can be evaluated by using which of the following techniques?
A. Analytic Evaluation and Simulations
B. Only Analytic Evaluation
C. Only Simulation
D. None of the above
Correct Answer:
A
Chapter: 17
Q444:
The main goal of using multilevel feedback queue scheduling is to manage __________ processes efficiently.
A. Interactive and I/O bound processes
B. CPU-bound processes
C. Process starvation
D. Quantum processes
Correct Answer:
A
Chapter: 17
Q445:
The Little's formula n = λ * W is used for __________.
A. Queuing network analysis
B. CPU-bound process evaluation
C. Scheduling queue priority analysis
D. Scheduling algorithm simulation
Correct Answer:
A
Chapter: 17
Q446:
The primary characteristic of UNIX System V scheduling algorithm is __________.
A. Round Robin within each priority band
B. Priority recalculation every second
C. Random scheduling of processes
D. FIFO scheduling of processes
Correct Answer:
A
Chapter: 17
Q447:
The efficiency of a scheduling algorithm is judged by __________.
A. CPU utilization, response time, and throughput
B. Only CPU utilization
C. Only response time
D. Only throughput
Correct Answer:
A
Chapter: 18
Q448:
What is the purpose of process synchronization?
A. To ensure data consistency
B. To improve system performance
C. To control CPU scheduling
D. To manage memory allocation
Correct Answer:
A
Chapter: 18
Q449:
What is a race condition in process synchronization?
A. A condition where multiple processes access shared data concurrently
B. A condition where processes execute in sequence
C. A condition where processes are in a deadlock state
D. A condition where processes have no access to shared resources
Correct Answer:
A
Chapter: 18
Q450:
In the producer-consumer problem, what does the variable 'counter' represent?
A. The total number of items produced
B. The total number of items consumed
C. The current index in the buffer
D. The total capacity of the buffer
Correct Answer:
A
Chapter: 18
Q451:
What is the main problem caused when both producer and consumer try to update the counter concurrently?
A. Buffer overflow
B. Race condition
C. Deadlock
D. Memory leak
Correct Answer:
B
Chapter: 18
Q452:
What is the value of the 'counter' after the producer and consumer execute concurrently with initial value 5?
A. 4
B. 5
C. 6
D. 7
Correct Answer:
A
Chapter: 18
Q453:
In the producer-consumer problem, what happens when the buffer is full?
A. The producer stops producing items
B. The consumer stops consuming items
C. The system crashes
D. The buffer automatically resizes
Correct Answer:
A
Chapter: 18
Q454:
In process synchronization, which of the following is a software-based solution to the critical section problem?
A. Hardware locks
B. Semaphores
C. Mutexes
D. Binary signals
Correct Answer:
B
Chapter: 18
Q455:
What does the 'critical section' refer to in process synchronization?
A. A section of code in a process where it can access shared data
B. A section of code that is executed before the process enters the queue
C. A section of code that performs system initialization
D. A section of code that manages inter-process communication
Correct Answer:
A
Chapter: 18
Q456:
What is the main issue with the solution that uses a shared variable 'turn' for process synchronization?
A. It doesn't ensure mutual exclusion
B. It does not allow for strict alternation between processes
C. It doesn’t meet the progress requirement
D. It violates the bounded waiting condition
Correct Answer:
C
Chapter: 19
Q457:
What is the purpose of using the 'turn' variable in the first algorithm for the critical section problem?
A. To ensure mutual exclusion
B. To signal that a process is ready to enter the critical section
C. To allow both processes to run concurrently
D. To maintain the buffer size
Correct Answer:
A
Chapter: 19
Q458:
Which of the following is true about the solution using the 'turn' variable?
A. It ensures mutual exclusion but does not satisfy the progress condition
B. It satisfies all the conditions of the critical section problem
C. It allows for both processes to execute in parallel
D. It ensures that one process always has to wait indefinitely
Correct Answer:
A
Chapter: 19
Q459:
In Algorithm 2, what does the 'flag' array represent?
A. The state of the shared resource
B. Whether a process is ready to enter its critical section
C. The status of mutual exclusion
D. The number of processes waiting for execution
Correct Answer:
B
Chapter: 19
Q460:
What is the issue with Algorithm 2 when both processes set their flags to 'true' simultaneously?
A. The processes get stuck in an infinite loop
B. The critical section is not entered
C. The processes execute out of order
D. The system crashes
Correct Answer:
A