this post was submitted on 07 Jul 2024
835 points (92.6% liked)
linuxmemes
21304 readers
1420 users here now
Hint: :q!
Sister communities:
- LemmyMemes: Memes
- LemmyShitpost: Anything and everything goes.
- RISA: Star Trek memes and shitposts
Community rules (click to expand)
1. Follow the site-wide rules
- Instance-wide TOS: https://legal.lemmy.world/tos/
- Lemmy code of conduct: https://join-lemmy.org/docs/code_of_conduct.html
2. Be civil
- Understand the difference between a joke and an insult.
- Do not harrass or attack members of the community for any reason.
- Leave remarks of "peasantry" to the PCMR community. If you dislike an OS/service/application, attack the thing you dislike, not the individuals who use it. Some people may not have a choice.
- Bigotry will not be tolerated.
- These rules are somewhat loosened when the subject is a public figure. Still, do not attack their person or incite harrassment.
3. Post Linux-related content
- Including Unix and BSD.
- Non-Linux content is acceptable as long as it makes a reference to Linux. For example, the poorly made mockery of
sudoin Windows. - No porn. Even if you watch it on a Linux machine.
4. No recent reposts
- Everybody uses Arch btw, can't quit Vim, and wants to interject for a moment. You can stop now.
Please report posts and comments that break these rules!
Important: never execute code or follow advice that you don't understand or can't verify, especially here. The word of the day is credibility. This is a meme community -- even the most helpful comments might just be shitposts that can damage your system. Be aware, be smart, don't fork-bomb your computer.
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Fake news.
Both Windows and Linux have their respective SIGTERM and SIGKILL equivalents. And both usually try SIGTERM before resorting to SIGKILL. That's what systemd's dreaded "a stop job is running" is. It waits a minute or so for the SIGTERM to be honoured before SIGKILLing the offending process.
Also fake because zombie processes.
I once spent several angry hours researching zombie processes in a quest to kill them by any means necessary. Ended up rebooting, which was a sort of baby-with-the bath-water solution.
Zombie processes still infuriate me. While I'm not a Rust developer, nor do I particularly care about the language, I'm eagerly watching Redox OS, as it looks like the micro kernel OS with the best chance to make to it useful desktop status. A good micro kernel would address so so many of the worst aspects of Linux.
Performance is the major flaw with microkernels that have prevented the half-dozen or more serious attempts at this to succeed.
Incurring context switching for low-level operations is just too slow.
An alternative might be a safe/provable language for kernel and drivers where the compiler can guarantee properties of kernel modules instead of requiring hardware guarantees, and it ends up in one address space/protection boundary. But then the compiler (and its output) becomes a trusted component.
Thank you. Came here to say this. Microkernels are great for limited scope devices like microcontrollers but really suffer in general computing.
Quite opposite. Most firmware microcontrollers run is giant kernel. Some microcontrollers don't even have context switching at all. And I'm not even starting to talk about MMU.
I was not meaning to say that all microcontrollers (or microcontroller firmwares) run a microkernel but, rather, that microcontrollers are an environment where they can work well because the limited scope of what the device is expected to do and its necessarily supported peripherals can be much smaller, making the potential impact of context changes smaller.
For some good examples of microkernels for such purposes, take a look at FreeRTOS, ChibiOS, or Zephyr pre-1.6 (at which point architecture changed to a monolith because it is creeping towards general computing functionality).
As long as there's some processing RAM and sufficient ROM, I'm sure that it can be crammed in there via firmware (in a sub-optimal way that makes people who have to maintain the code, including your future self, hate you and wish a more appropriate part were used).
Some madlads forked Linux to get it to work without an MMU, even getting it merged into the mainline kernel: https://en.m.wikipedia.org/wiki/%CE%9CClinux
So, doable. Adviseable? Probably not in most cases but that's subjective.
AFAIK FreeRTOS always ran drivers in kernel.
You can't even emulate MPU without MPU. The only way is running bytecode, which is still not context switching.
You are correct here. Should have said MPU instead.
At least in the docs, I see it described as a microkernel but, with a kernel that small, the differences are probably academic (and I'll leave that to people with more formal background in CS than myself).
Oh yes! That makes a lot more sense. I've been on-and-off looking at implementing multithreading and multiprocessing in CircuitPython. Memory protection is a big problem with making it work reliably.
Then you would need to move compiler to kernel. Well, there is one: BPF(and derivatives). It's turing-incomplete by design.