Tenta

Question 1

What are the main components of a computer system?

Answer 1

CPU, Memory (RAM/ROM), Input/Output Devices, and System Bus

Question 2

What is the difference between volatile and non-volatile memory?

Answer 2

Volatile memory (e.g., RAM) loses data when powered off; non-volatile memory (e.g., SSD, HDD) retains data.

Question 3

How does an operating system provide resource abstraction?

Answer 3

It hides the complexity of hardware by providing standardized interfaces (e.g., file systems, virtual memory).

Question 4

Can a single-core CPU run multiple programs simultaneously?

Answer 4

Yes, via time-sharing. The CPU switches between tasks rapidly.

Question 5

Name two mechanisms operating systems use to ensure protection in multiprogramming.

Answer 5

1) User and Kernel Modes, 2) Access Control via Permissions.

Question 6

What are the steps of the processor instruction cycle?

Answer 6

Fetch, Decode, Execute, Store.

Question 7

Describe the difference between stack-based and register-based architectures.

Answer 7

Stack-based uses a last-in, first-out stack for operations; register-based uses general-purpose register

Question 8

What are the advantages of a stack-based architecture?

Answer 8

Simplified instruction set and no need to manage register allocation manually.

Question 9

What is the role of an interrupt in process management?

Answer 9

Interrupts allow the CPU to pause a running process and handle an urgent task (e.g., I/O operation

Question 10

What is a race condition in synchronization?

Answer 10

A situation where multiple processes access shared resources concurrently, leading to unpredictable results.

Question 11

Name two techniques to prevent deadlock.

Answer 11

1) Avoiding circular wait, 2) Resource allocation graphs.

Question 12

In the Five-State Process Model, what happens during a “Blocked to Ready” transition?

Answer 12

A waiting process receives the needed resource or event signal and is ready to execute.

Question 13

Why would you recommend stack-based architecture for teaching kids?

Answer 13

Simple execution model and less overhead, making it easier to understand basic programming concepts.

Question 14

Why are smaller unit allocation sizes not always ideal for file storage?

Answer 14

They reduce internal fragmentation but increase metadata overhead.

Question 15

For a self-driving car, which device communication method should you use?

Answer 15

Interrupt-driven communication for real-time responsiveness to human inputs (e.g., braking).

Question 16

How would you avoid race conditions in a deposit and withdrawal system?

Answer 16

Use locks to synchronize access and ensure atomic operations. Avoid deadlocks by acquiring locks in a consistent order.

Question 17

Why is multiprogramming useful in operating systems?

Answer 17

Increases CPU utilization by overlapping I/O-bound and CPU-bound tasks.

Question 18

What is the role of the operating system?

Answer 18

It interfaces between the user’s program and hardware, providing resource sharing, abstraction, security, and performance optimization

Question 19

What are the types of instructions in the CPU?

Answer 19

Data Transfer Instructions: Move data between locations.

Data Operation Instructions: Perform operations on data (e.g., add, subtract).

Program Control Instructions: Control program flow (e.g., jumps, interrupts).

Question 20

Compare Stack-based and General Purpose Register (GPR) architectures.

Answer 20

Stack-based: Smaller code size, automatic register management, good for embedded systems.

GPR: Better performance with compilers, allows explicit register management, used in modern computers.

Question 21

How does a stack-based architecture handle operands?

Answer 21

Operands are pushed to or popped from the stack, with results also stored on the stack.

Question 22

How does a GPR architecture handle operands?

Answer 22

Operands are stored in registers specified in the instruction (e.g., ADD r1, r2, r3).

Question 23

What are the advantages of stack-based architectures?

Answer 23

Compact code size.

Simplifies program design by avoiding manual register allocation.

Question 24

What are the advantages of GPR architectures?

Answer 24

Higher performance due to compiler optimizations.

Flexible operand handling using registers.

Question 25

What is a process?

Answer 25

A program in execution, consisting of:

Program.

Data.

Process Control Block (PCB).

Question 26

What are the five states in the Five-State Process Model?

Answer 26

New, Ready, Running, Blocked, Terminated.

Question 27

Why are suspended processes used?

Answer 27

To free up memory when all processes are waiting for I/O operations

Question 28

What is a Process Control Block (PCB)?

Answer 28

A data structure containing information about the process, such as its state, program counter, and resources.

Question 29

What are cooperative and preemptive schedulers?

Answer 29

Cooperative: Processes voluntarily yield the CPU.

Preemptive: CPU is forcibly taken from a process using an interrup

Question 30

What is the aim of scheduling?

Answer 30

To ensure efficiency, fairness, and system responsiveness.

Question 31

What are MLQ and MLQF scheduling?

Answer 31

MLQ (Multi-Level Queue): Divides processes into different priority levels.

MLQF (Multi-Level Queue with Feedback): Allows processes to move between queues based on execution characteristics.

Question 32

What are the four conditions for deadlock?

Answer 32

Mutex: Non-shareable resources.

No pre-emption: Resources cannot be forcibly taken.

Hold and wait: A process holds one resource while waiting for another.

Circular wait: A circular chain of processes exists, each waiting for a resource held by another.

Question 33

What is a semaphore?

Answer 33

A synchronization primitive used to manage access to shared resources using wait() and signal() operations.