Operating systems MCQ questions set 1 for competitive exams



Operating systems multiple choice questions


1. The Dining Philosophers is an example of:
a. A bounded buffer problem
b. A synchronization problem
c. A readers/writers problem

2. Semaphores are used for:
a. Resource abstraction and resource sharing
b. Data hiding and encapsulation
c. Mutual exclusion and synchronization

3. A critical region is:
a. The part of a program in which shared data is accessed.
b. The most important part of a program
c. The part of the kernel that interfaces to the device controllers        

4. System calls:
a. Provide a rich and flexible API for software developers to use
b. Protect important kernel data structures from user code
c. Increase the performance of the operating system

5. In a user-level thread package, threads are scheduled by:
a. The kernel
b. The user
c. The process

6. Multi-programming (vs. multitasking) allows the operating system to
a. interrupt a process to run another process.
b. switch execution to another process when the first process blocks on I/O or makes a system call.
c. allow a single process to take advantage of multiple processors.
d. distribute multiple processes across multiple processors in a system.

7. A semaphore puts a thread to sleep
a. if it tries to decrement the semaphore's value below 0.
b. if it increments the semaphore's value above 0.
c. until another thread issues a notify on the semaphore.
d. until the semaphore's value reaches a specific number.

8. The main difference between paging and segmentation is:
a. The size of the objects being managed
b. One refers to memory and the other refers to disk
c. Nothing; they are two names for the same thing

9. A processor switches execution from user mode to privileged mode via:
a. a software interrupt.
b. a programmable I/O.
c. a hardware interrupt.
d. memory mapped I/O.

10. Implementing preemption in operating systems relies on:
a. a programmable interval timer.
b. being able to switch to kernel mode.
c. having a modular operating system design.
d. programmable I/O.


*********