Skip to main content

Micro kernel architecture

 Micro kernel architecture

What is Kernel?

A kernel is an important part of an OS that manages system resources. It also acts as a bridge between the software and hardware of the computer. It is one of the first program which is loaded on start-up after the bootloader. The Kernel is also responsible for offering secure access to the machine's hardware for various programs. It also decides when and how long a certain application uses specific hardware.

What is Microkernel?

Microkernel is a software or code which contains the required minimum amount of functions, data, and features to implement an operating system. It provides a minimal number of mechanisms, which is good enough to run the most basic functions of an operating system. It allows other parts of the operating system to be implemented as it does not impose a lot of policies.

Microkernels and their user environments are usually implemented in the C++ or C programming languages with a little bit of assembly. However, other implementation languages are possible with some high-level coding.

What is a Monolithic Kernel?

Monolithic Kernel runs all the basic system services like process management, Memory management, I/O communication, and interrupt handling, file system, etc in kernel space.

In this type of Kernel approach, the entire operating system runs as a single program in kernel mode. The operating system is written as a collection of procedures that are linked together into a large executable binary program.

1. Monolithic architecture

2.    Layerd archtecture.

3.     Virtual machine architecture

4.     Exokernel architecture

5.    Client server architecture 

6.     Micro kernel architecture

Microkernel Architecture

A Microkernel is the most important part for correct implementation of an operating system. You can see in the below-given diagram, that Microkernel fulfills basic operations like memory, process scheduling mechanisms, and inter-process communication.

Microkernel Based Operating System

Microkernel is the only software executing at the privileged level. The other important functionalities of the OS are removed from the kernel-mode and run in the user mode. These functionalities may be device drivers, application, file servers, interprocess communication, etc.

Components of Microkernel

A microkernel comprises only the core functionalities of the system. A component is included in the Microkernel only if putting it outside would interrupt the functionality of the system. All other non-essential components should be put in the user mode.

The minimum functionalities required in the Microkernel are:

  • Memory management mechanisms like address spaces should be included in the Microkernel. It also contains memory protection features.
  • Processor scheduling mechanisms should contain process and thread schedulers.
  • Inter-process communication manages the servers that run their own address spaces.

Difference Between Microkernel and Monolithic Kernel

ParametersMonolithic kernelMicroKernel
BasicIt is a large process running in a single address spaceIt can be broken down into separate processes called servers.
CodeIn order to write a monolithic kernel, less code is required.In order to write a microkernel, more code is required
SecurityIf a service crashes, the whole system collapses in a monolithic kernel.If a service crashes, it never affects the working of a microkernel.
CommunicationIt is a single static binary fileServers communicate through IPC.
ExampleLinux, BSDs, Microsoft Windows (95,98, Me), Solaris, OS-9, AIX, DOS, XTS-400, etc.L4Linux, QNX, SymbianK42, Mac OS X, Integrity, etc.

Advantages of Microkernel

Here, are the pros/benefits of using Microkernel

  • Microkernel architecture is small and isolated therefore it can function better.
  • Microkernels are secure because only those components are included that disrupt the functionality of the system otherwise.
  • The expansion of the system is more accessible, so it can be added to the system application without disturbing the Kernel.
  • Microkernels are modular, and the different modules can be replaced, reloaded, modified without even touching the Kernel.
  • Fewer system crashes when compared with monolithic systems.
  • Microkernel interface helps you to enforce a more modular system structure.
  • Without recompiling, add new features
  • Server malfunction is also isolated as any other user program's malfunction.
  • Microkernel system is flexible, so different strategies and APIs, implemented by different servers, which can coexist in the system.
  • Increased security and stability will result in a decreased amount of code which runs on kernel mode

Disadvantage of Microkernel

Here, are drawback/cons of using Microkernel:

  • Providing services in a microkernel system are expensive compared to the normal monolithic system.
  • Context switch or a function call needed when the drivers are implemented as procedures or processes, respectively.
  • The performance of a microkernel system can be indifferent and may lead to some problems.

Summary:

  • A kernel is an important part of an OS that manages system resources.
  • A microkernel is a software or code which contains the required minimum amount of functions, data, and features to implement an operating system.
  • In Monolithic Kernel approach, the entire operating system runs as a single program in kernel mode
  • A Microkernel is the most important part for correct implementation of an operating system.
  • A microkernel comprises only the core functionalities of the system.
  • A monolithic kernel is a large process running in a single address space, whereas Microkernel can be broken down into separate processes called servers.
  • Microkernel architecture is small and isolated therefore it can function better
  • Providing services in a microkernel system are expensive compared to the normal monolithic system.

Comments

Post a Comment

Popular posts from this blog

Defination of OS(operating system) and its concepts

    What do you mean by operating system?     Definition :  An operating system is a program that act as an interface between the user of a computer and the                                      Computer hardware. Operating system is a first program that gets loaded into the memory through a process called booting. Concepts of operating system : ·                       The purpose of operating system is to provide an environment in which a user can execute program in a convenient and efficient manner. ·                       Operating system is an integrated set of program that ma...
3 comments
Read more

Monolithic Architecture

  Monolithic Architecture Monolith means composed all in one piece. The  Monolithic  application describes a single-tiered  software  application in which different components combined into a single program from a single platform. Components can be: Authorization — responsible for authorizing a user Presentation — responsible for handling HTTP requests and responding with either HTML or JSON/XML (for web services APIs). Business logic — the application’s business logic. Database layer — data access objects responsible for accessing the database. Application integration — integration with other services (e.g. via messaging or REST API). Or integration with any other Data sources. Notification module — responsible for sending email notifications whenever needed. Example for Monolithic Approach Consider an example of Ecommerce application, that authorizes customer, takes an order, check products inventory, authorize payment and ships ordered products. This applicat...
Post a Comment
Read more

System structure operating architecture

  System structure operating  architecture An operating system is a construct that allows the user application programs to interact with the system hardware. Since the operating system is such a complex structure, it should be created with utmost care so it can be used and modified easily. An easy way to do this is to create the operating system in parts. Each of these parts should be well defined with clear inputs, outputs and functions. Simple Structure There are many operating systems that have a rather simple structure. These started as small systems and rapidly expanded much further than their scope. A common example of this is MS-DOS. It was designed simply for a niche amount for people. There was no indication that it would become so popular. An image to illustrate the structure of MS-DOS is as follows − It is better that operating systems have a modular structure, unlike MS-DOS. That would lead to greater control over the computer system and its various applications. T...
Post a Comment
Read more

Classification of Operating System

  Classification of operating systems The operating systems may be classified into different types depending upon the nature of interaction between the user and his/her program. The various types of operating system are : 1.       single user operating system    2.        Multi user operating system   3.         Batch processing operating system 4.        Multi programming operating system   5.       Multi tasking operating system   6.         Multiprocessing operating system 7.         Time sharing operating system 8.       Real time system      Distributed system Multi threading operating system       Single user operating system ·          ...
Post a Comment
Read more

Change the priority of a process

  Change the priority of a process You can tell the computer that certain processes should have a higher priority than others, and so should be given a bigger share of the available computing time. This can make them run faster, but only in certain cases. You can also give a process a  lower  priority if you think it is taking up too much processing power. Go to the  Processes  tab and click on the process you want to have a different priority. Right-click the process, and use the  Change Priority  menu to assign the process a higher or lower priority. There is typically little need to change process priorities manually. The computer will usually do a good job of managing them itself. (The system for managing the priority of processes is called  nice .) Does higher priority make a process run faster? The computer shares its processing time between all of the running processes. This is normally shared intelligently, so programs that are doing more ...
Post a Comment
Read more