this post was submitted on 07 Mar 2024
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Linux

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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.

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[–] [email protected] 35 points 8 months ago (4 children)

I watched a video on this, the way they managed it was by reordering variables in structs. That’s kinda insane

[–] [email protected] 12 points 8 months ago

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.

[–] [email protected] 4 points 8 months ago (1 children)
[–] [email protected] 4 points 8 months ago

Not a surprise, considering the amount of data and processes the kernel manages.

[–] [email protected] 3 points 8 months ago* (last edited 8 months ago)

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!