AMCAT Operating Systems Fundamentals 2

Question 1

Which page replacement algorithm is known as the optimal algorithm but is impractical for real-time use?

Accepted Answer

Optimal Page Replacement (OPT/Belady's)

Answer

First In First Out (FIFO)

Answer

Least Recently Used (LRU)

Answer

Clock Algorithm

Question 2

What is the main advantage of a multilevel feedback queue scheduling algorithm?

Accepted Answer

It can adapt to the behavior of processes by moving them between queues of different priorities

Answer

It uses only one queue, making it simple to implement

Answer

It guarantees that all processes finish in the same amount of time

Answer

It eliminates the need for context switching

Question 3

In a system using demand paging, when is a page loaded into memory?

Accepted Answer

Only when the page is actually accessed and causes a page fault

Answer

When the process is first created

Answer

When all pages of the process are needed

Answer

At regular time intervals determined by the scheduler

Question 4

What is the Banker's Algorithm used for in operating systems?

Accepted Answer

Deadlock avoidance by determining if resource allocation will leave the system in a safe state

Answer

Memory allocation and defragmentation

Answer

CPU scheduling and time-sharing

Answer

File system management and disk scheduling

Question 5

Which of the following best describes thrashing in an operating system?

Accepted Answer

The system spending most of its time swapping pages in and out of memory rather than executing processes

Answer

A process running at maximum CPU utilization

Answer

A deadlock between multiple processes

Answer

Excessive use of CPU cache

Question 6

What is the difference between preemptive and non-preemptive scheduling?

Accepted Answer

In preemptive scheduling, a running process can be interrupted and moved to ready state; in non-preemptive, a process runs until it voluntarily yields or completes

Answer

Preemptive scheduling does not use a timer; non-preemptive scheduling does

Answer

Non-preemptive scheduling is always faster than preemptive scheduling

Answer

Preemptive scheduling only works with single-core processors