subsystem in the kernel context

[shaharhada]

The Linux kernel is constantly growing, with 20 million lines of code in 2018. From a foundational level, this kernel is layered into a variety of subsystems.
In the source:
https://www.techtarget.com/searchdatacenter/definition/kernel
under the title Types of kernels
What are subsystems?

 

[Ralston18]

From the link:

"These main groups include a system call interface, process management, network stack, memory management, virtual file system, arch and device drivers. "

Each of those groups being a "subsystem".

The advantage of subsystems is that changes can be made within any given subsystem, memory management for example, without needing to make changes to the entire system or other subsystems.

And there can be subsystems within subsystems.....layers.

Deciding on and planning for subsystems is often part of the design process.

As another example if you have a Linux OS and need to change physical printer you only have to change the "printer subsystem" - the printer drivers.

Not rewrite the entire Linux OS.

 

[shaharhada]

From the link:

"These main groups include a system call interface, process management, network stack, memory management, virtual file system, arch and device drivers. "

Each of those groups being a "subsystem".

The advantage of subsystems is that changes can be made within any given subsystem, memory management for example, without needing to make changes to the entire system or other subsystems.

And there can be subsystems within subsystems.....layers.

Deciding on and planning for subsystems is often part of the design process.

As another example if you have a Linux OS and need to change physical printer you only have to change the "printer subsystem" - the printer drivers.

Not rewrite the entire Linux OS.

Can you explain your last sentence. (I'm not English speaker).
Not rewrite the entire Linux OS.

 

[USAFRet]

Can you explain your last sentence. (I'm not English speaker).
Not rewrite the entire Linux OS.

Like the tires on a car.
Each tire may be considered a "subsystem".

If you need to change tires, no need to rebuild the entire car.

 

[shaharhada]

Thanks from my deep heart to both of you.