Kernel & User Space

Question 1

How many modes Does a computer has and name them.

Answer 1

User Mode

Kernel Mode

Question 2

User Mode

Answer 2

Applications Run in user mode. This run in private virtual address space. Each application has its own space and if it crashes only that application crashes.

Question 3

Kernel Mode

Answer 3

System components run in kernel mode. All code that run in kernel model shares a single virtual address space.

Question 4

Draw the separation of User mode and kernel mode.

Answer 4

Application API ||| Drivers Hardware.

Question 5

What are the standard run levels and their #..

Answer 5

0 – shutdown

1 – Run single mode

6 – reboot

Question 6

How many linux run levels are there? and name them.

Answer 6

0 - System halt. The system could be shut down

1 - Single User Mode

2 - Multiple user mode with no NFS

3 - Multiple user mode under the command line interface and no under GUI

4 - user definable

5 - Multiple user mode under guidelines and this is the stand run level for most of the linux based systems.

6 - Reboot which is used to restart the system