ICT Operating System Fundamentals 4

Question 1

What distinguishes a microkernel architecture from a monolithic kernel?

Accepted Answer

Microkernels keep only essential functions in kernel space and run services in user space

Answer

Microkernels minimize the kernel by running services like file systems and drivers in user space, improving modularity.

Question 2

What happens during a context switch?

Accepted Answer

The CPU saves the current process state and loads the state of the next scheduled process

Answer

A context switch saves the PCB of the running process and restores the PCB of the next process to run.

Question 3

Which page replacement algorithm has the lowest page fault rate theoretically?

Accepted Answer

Optimal (OPT)

Answer

The Optimal algorithm replaces the page that will not be used for the longest future time, minimizing page faults.

Question 4

In Unix, what does the 'fork()' system call return to the parent process?

Accepted Answer

The PID of the child process

Answer

fork() returns the child's PID to the parent, and 0 to the child — allowing each to identify its role.

Question 5

What is the purpose of a 'mutex' (mutual exclusion lock)?

Accepted Answer

To ensure only one thread accesses a critical section at a time

Answer

A mutex ensures that only one thread can hold the lock and execute within the critical section at any given time.

ICT - Information Communication Technology Practice Test