A kernel is the core program that manages CPU resources, system devices, system memory, file systems, and networking

1. Kernel Computing
By,
M. Sabiha
120419862042
MCA II Year

2. Whenever while discussing about PCs &
Laptops, you might come across the term…

3. What is the
Kernel?
Why is it
important?
Where it has
come from?

4. A computer is a machine which needs only the instructions to
execute it’s tasks.
From the moment it starts booting, it needs instructions.
Without instructions it can’t do anything.
As soon as the computer screen is booted and starts showing
the Windows logo, (with a nice 4 color window), there is
something more going on that cannot meet the eye.

5. Java Virtual Machine
It is the one which is responsible for
doing all the different things which are
displayed on the screen.

6. To understand more clearly, let’s have a look on the
overall structure which is happening
behind the scene

7. LINUX KERNEL
LIBRARIES
Surface
Manager
Media
Framework
SQLite WebKit SGL SSL
APPLICATION FRAMEWORK
Activity
Manager
Window
Manager
Notification
Manager
Package
Manager
Resource
Manager
Location
Manager
APPLICATIONS
Home Contacts Phone Browser

8. Linux Kernel
Display Driver Camera Driver
Bluetooth
Driver
Flash Memory
Driver
USB Driver Keypad Driver
Wi-Fi Driver Audio Drivers
Power
Management

9. What is Kernel?

10. KERNEL
CPU
Resources
System
Devices
System
Memory
File
Systems
Networking
A kernel is the core program which manages …

11. This means that when you start an app…
Loads the
app into
memory
Creates
the
processes
Starts the
app
running

12. 1. When app needs memory, it is the kernel that allocates it.
2. When the app wants networking, it is the kernel which does
all the low level processing.
3. When the app wants to perform a task in the background, it
is the kernel which handles the background threads.
4. When the app closes, it is the kernel which cleans up all the
memory and other resources that were used by the app.

13. Types of Kernel

14. Kernel
Monolithic
Kernel
Micro
Kernel
Hybrid
Kernel
Exo Kernel
Nano
Kernel

15. 1. Monolithic
Kernel
•Where all operating system services operate in kernel space.
•Huge lines of complex code.
•Example: Unix and Linux.
2. Micro
Kernel
•Least approachable.
•More stable with less services in kernel space.
•Has virtual machine and thread scheduling.
•Example: Mach and AmigaOS.
3. Hybrid
Kernel
•Combination of both monolithic and micro kernel.
•Has speed and design of monolithic kernel.
•Has modularity and stability like micro kernel.
•Example: Windows NT and Netware.
4. Exo Kernel
•Follows end-to-end principle.
•Has fewest hardware abstractions.
•Allocates physical resources to applications.
•Example: Nemesis and ExOS.
5. Nano
Kernel
•Provides hardware abstraction without system services.
•Rarely used and thus, it is analogous.
•Example: EROS.

16. Kernel Space and User Space

17. Virtual Machine
Kernel Space User Space
Basically,
It is the area in virtual
memory where
kernel processes will run
It is the area in virtual
memory where
user processes will run

19. Some important points…
1. A modern computer operating system usually segregates virtual
memory into kernel space and user space.
2. This separation serves to provide memory protection and hardware
protection from malicious or errant software behaviour.
3. Kernel space is strictly reserved for operating system kernel extensions,
and most device drivers.
4. User space is the memory area where application software and some
related drivers execute.
5. The most common way of implementing user mode instead of kernel
mode involves operating system protection rings

20. Latest news on Kernel Computing

21. Google Finally Begins Their Open-Source Around Linux User-Space Threading
1. Way back in 2013 there was a presentation at the Linux Plumbers
Conference around Google's work on user-level threads and how they
were working on new kernel functionality for using regular threads in
a cooperative fashion and building various features of that.
2. Today, that functionality has been in use internally at Google for a
range of services for latency-sensitive services and greater control
over user-space scheduling while now finally in 2020 they are
working towards open-sourcing that work.

22. Points To Remember

23. 1. Kernel is the central part of the operating system that manages the resources
including memory, processes and various drivers.
2. All multitasking operating systems have a kernel.
3. The rest of the operating system, whether it be Windows, OS X, iOS, or Android, is
built on top of the kernel.
4. Many kernels are also responsible for ensuring that faulty programs do not interfere
with the operation of others by denying access to memory that has not been allocated
to them and restricting the amount of CPU time they can consume.

24. HARDWARE DEVICES
DEVICE DRIVERS
FILE SYSTEM & USER
INTERFACE
APIs
KERNEL