this post was submitted on 16 Feb 2024
995 points (99.3% liked)

linuxmemes

20880 readers
4 users here now

I use Arch btw

Sister communities:

Community rules

  1. Follow the site-wide rules and code of conduct
  2. Be civil
  3. Post Linux-related content
  4. No recent reposts

Please report posts and comments that break these rules!

founded 1 year ago
MODERATORS
[email protected]
[email protected]
[email protected]
995
Htop too (lemm.ee)
submitted 9 months ago by [email protected] to c/[email protected]
35 comments fedilink hide all child comments
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 10 points 9 months ago* (last edited 9 months ago) (2 children)

I think a lot of modern kernels are “tickless” - they don’t use a timeslice timer, and only context switch on IO interrupt, process yield, or when timeouts are specifically requested (including capping cpu-bound processes). https://en.m.wikipedia.org/wiki/Tickless_kernel

[–] [email protected] 18 points 9 months ago (1 children)

Tickless means it’s not based on the computer frequency and idle CPUs can stay idle rather than being annoyingly brought into high power mode ever 100 Hz, but it’s still firing interrupts based on scaling timed variables.

They’re now called “Dynticks”

SUSE wrote the vaguely more understandable write up that Linux foundation links to: https://www.suse.com/c/cpu-isolation-full-dynticks-part2/

BTW, the Linux RCU code is evil but interesting: https://www.p99conf.io/session/how-to-avoid-learning-the-linux-kernel-memory-model/

[–] [email protected] 5 points 9 months ago

Fascinating stuff. Obviously a lot has changed since I took an undergrad OS class lol. Hell, Linux didn't even exist back then.