this post was submitted on 07 Mar 2024
282 points (99.6% liked)
Linux
48318 readers
947 users here now
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
Rules
- Posts must be relevant to operating systems running the Linux kernel. GNU/Linux or otherwise.
- No misinformation
- No NSFW content
- No hate speech, bigotry, etc
Related Communities
Community icon by Alpár-Etele Méder, licensed under CC BY 3.0
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
I watched a video on this, the way they managed it was by reordering variables in structs. That’s kinda insane
Reordering members can lead to better packing and a smaller memory footprint, due to how alignment works. If you're iterating a large number of objects, having smaller objects is very favorable in terms of cache locality; you get fewer cache misses, and prefetching is more effective.
For the curious: pahole is a very useful tool for this type of code analysis.
Can you link video?
Probably this is the video https://www.youtube.com/watch?v=qo1FFNUVB-Q
Not a surprise, considering the amount of data and processes the kernel manages.
Oh to increase cache hits?
Edit: Ok I read the article, yes more cache hits. It's neat how they put more context for the title in the link in case one gets curious about it!