The Bizarre Case Of Zstd's Very Slow Performance On Arch Linux

[phoronix]

Phoronix: The Bizarre Case Of Zstd's Very Slow Performance On Arch Linux

Yesterday I posted benchmarks of six Linux distributions on the HP Dev One, the exciting new Linux laptop launched by HP in collaboration with System76 that is using their Pop!_OS distribution. From those benchmarks one of the bizarre findings was that the Zstd compression performance on Arch Linux simply sucked, but some interested developers dove in and found the rather bizarre culprit why their Zstd performance is so poor in relation to other Linux distributions on the same version...

https://www.phoronix.com/scan.php?page=news_item&px=Arch-Linux-Bizarre-Zstd

[bug77]

So how the heck is the build system interfering with the resulting binary performance if it's not an optimization level difference?

The CMake build system for Zstd ends up adding the "-std=c99" flag

Turns out there is some sort of optimization level difference.
I'm curious whether this unearths some inefficiency/overhead in the C99 target, paving the way for more generic performance gains.

[guglovich]

QA, knock-knock

[Retramon]

Compare both versions in ASM and see the diff ... also, could be some kind of a CPU HW trick doing something differently under the hood.

[Danny3]

Shouldn't the Zstd' compress / decompress functions be implemented into the Linux kernel or the GNU C library and they only be called by the desktop environment / file manager/ programs / games when need it?

Why is it at the distro level?

Now I wonder why after almost half a year after the last Zstd release the Zstd code in the Linux kernel still has not been upgraded to it...
They said last time that they made it easier to keep it in sync with the upstream Zstd releases, but it looks like they abandoned the idea and the Zstd in the kernel is outdated again.

[neoe]

So wait for another article after figured out why "-std=C99" result slowing.

[skeevy420]

80 Minutes Ago - Arch Linux - Arch Linux + Zstd = Bad?

What kind of math is that?

But very interesting results over the C standard flag. Makes ya wonder what else could be improved by things like that.

[Vorpal]

Michael hi! Some corrections:

• Meson is also slow.
• I (Arvid Norlander) am an arch user, not a developer. I do have a background in software development though. I have no idea if Antonio Rojas is a dev or user.

[jacob]

This is why personally I never advocated or used source based distros like Gentoo.

[skeevy420]

Michael hi! Some corrections:

• Meson is also slow.
• I (Arvid Norlander) am an arch user, not a developer. I do have a background in software development though. I have no idea if Antonio Rojas is a dev or user.

I know he's an Arch package maintainer. He closed one of my bugs.

I agree with your assessment about the multiple build system silliness.