If you have used a modern computer or smartphone, you might have encountered errors related to kernel. Kernel-related errors are common in computers and smartphones, and every operating system manifested the errors differently.
In Windows, kernel errors are displayed to the users as Blue Screen of Death (BSoD), and Unix-based operating systems (such as Linux, Android, and Mac OS X) throws in “kernel panic” error every time a kernel-related errors happened.
However, you might question, “What is the function of the kernel in the operating system? Is it critical to the overall operation of the computer/smartphone?”
And the answer of that question is a resounding “yes”. Kernel is a very important piece of your operating system.
So, What is the Function of Kernel in an Operating System?
When you turn on your computer, the first thing it loaded is the BIOS, then the bootloader which will call the operating system. Afterwards, the kernel is loaded, which is responsible for bridging the communication between the operating system (software) to your hardware.
As the kernel is important to the stability of the operating system, it is often loaded into a separate memory area, which cannot be overwritten by other programs or processes.
After the kernel is loaded and operating system is booted, the kernel is responsible to decide, every time, the resource allocation to the programs.
For example, a processor-intensive program could request more CPU power to the operating system through the kernel. Not only CPU access, the kernel also manages memory access to the programs.
Types of Kernel
There are various types of kernel: monolithic, hybrid/modular, and microkernel. Each types of kernel have their own appropriate use cases.
Monolithic kernel is loaded entirely in the same address space, known as kernel space. This is done to increase performance and efficiency.
Some operating systems, such as Linux and BSD, also allow for modularity, in which they can load kernel modules (like drivers) dynamically. This allows for greater speed and as such, the approach is suitable for a wide range of system.
Hybrid kernel, on the other hand, shares characteristics from monolithic kernel and microkernel.
The main examples of operating systems using hybrid kernel are Windows NT family (up to and including Windows 10) and XNU (X is not Unix) family used by Apple to power macOS, iOS, watchOS, and tvOS.
In Windows NT family, the kernel runs some services in the kernel space in order to reduce performance overhead found in microkernel.
However, some kernel code is still available in the user space. That way, hybrid kernel could achieve the performance of monolithic kernel with the stability of microkernel.
So, to sum up, do you need to worry about the kernel type that is running on your operating system? No, you do not need to.
In most operating systems, kernel updates are tied to version update, and you can upgrade your kernel by updating your operating system.
However, if you use Linux or BSD, you can actually build and use a custom kernel if needed. Consult your operating system manual if you feel unsure about this.