How and where to see how the operating system works?

Question

Operating Systems

Good afternoon. I am reading the book "Modern operating systems. E. Tanenbaum". While reading up to memory management. Everything seems to be very abstract. There are few examples in the book. Maybe someone knows how to look at the insides of the OS, see how it works?

Answer 1

open the system unit and see... :)
but seriously, modern operating systems are a complex mechanism that is difficult to describe with some models, let alone see them. plus you still need to decide what to watch - I / O devices, kernel, memory, etc. after all, many different software gears spin in the OS. maybe try to deal with minix, which tannenbaum taught as a basis at the university sometime in his years .... well, or take the simplest Linux. Of course, the question is what OS do you want to see, monolith, RTOS, etc.? study more theory, and for practice, disassemble source codes, program, write simple test utilities, well, each OS has its own debuggers-toolkits-utilities with which you can dig deeper into memory, registers, sockets, processes, threads, threads, threads, mutexes, semaphores, forks,

Answer 2

For concretization with this book, read the book by Tanenbaum and Woodhull "Operating Systems: Design and Implementation". In it, practice on the example of the training OS Minix. Or you can take the example of another educational OS Xv6 -
. Commented source codes are attached to it.
And I do not advise you to take up a debugger right away. There is a risk of losing interest in this topic.

Answer 3

I remember a quote from a famous movie:
- Look in the dog.
- How is it - look in the dog?
Well, I mean, open it up.
“Fuck it, it’s not a can of beans, what do you mean “open it”?!
It’s also about here, you can measure a bunch of characteristics, any metrics and indicators, but it’s probably impossible to see how it works, even knowing the entire structure.
There is a good video from Yandex , talks about utilities with which you can theoretically see a lot.

Answer 4

how to look at the internals of the OS, see how it works?

Load linux into qemu and walk around it with gdb. For example: www.linux-magazine.com/Online/Features/Qemu-and-th...

Answer 5

I first read "The Design and Implementation of the FreeBSD Operating System". There, too, it is well and interestingly written about the internal mechanisms of FreeBSD.
I managed to try all this on real hardware by purchasing a board with an AT91SAM9XE512 ARM processor. It was on it that it turned out to independently configure and run the MMU, memory protection, multithreading and work with system calls (without using ready-made operating systems). I wanted to write an article about it. Then I found the qemu emulator, in which you can do the same, but without buying hardware.

Answer 6

Access to the memory manager is closed and you can't easily look at the request queue for allocating memory on the stack or heap. What exactly do you want to see?

Answer 7

windbg?