All you need to know about Kernel...

This post explains very briefly what all you need to know about the kernel, types of the kernel and the differences between user space and kernel space.

      crux points of Kernel:

1. The kernel is the core of an operating system. Without Kernel, OS is of no use.
2. All other components rely on the kernel.
3. The kernel manages file system access, memory, processes, devices and resource allocation on a system.
4. The kernel also controls hardware devices plugged into the system.
5. It is one of the first elements to be loaded on startup and remains in memory during the computer's operation.
6. The kernel also contains system-level commands and other functions that are normally hidden from users.

Now that you've understood what actually a kernel is, let's learn about user space and kernel space.
      
      crux points of User Space and Kernel Space:

1. Kernel tends to divide the software running in memory into two spaces-User Space and Kernel Space.
2. Kernel Space is simply space where kernel executes the services that it provides.
3. The User Space is the area of memory outside the kernel space.
4. Userspace can include everything from high-level applications that user interacts with directly to processes that run in the background and to various low-level system libraries.
5. Software running in user space can be able to access resources provided by kernel space through the use of system calls. These system calls provide the user-space application with the resources it needs to perform a task.
6. The split between these memory regions is useful because it promotes greater stability and security.
7. The software in one space cannot necessarily interact with the software in the other space.

Now that you've understood the difference between user space and kernel space, let's learn about the types of the kernel.

      crux points of Types of Kernels:

1. Kernels can be classified into two types-Monolithic Kernel and MicroKernel.
2. In a Monolithic Kernel, all system modules, such as device drivers or file systems run in kernel space. As a result, the monolithic kernel can interact quickly with devices.
3. However, its main disadvantage is its size, which leads to higher consumption of RAM. In addition, a failure in a device driver can lead to system instability in a monolithic kernel.
4. In MicroKernel architecture, the kernel itself runs the minimum amount of resources necessary to actually implement a fully functional operating system.
5. When compared to monolithic kernels, microkernels have smaller kernel space and larger user space.
6. This means microkernels are smaller in overall size and consume less memory. In addition, they are typically more stable. 
7. However, microkernels tend to offer worse performance than monolithic kernels.

Cheers! we have covered a whole lot in this post. This is probably the first post of my blog which is so lengthy!!