Mesa 24.2 Released With New Vulkan Extensions, New Shader Cache

[phoronix]

Phoronix: Mesa 24.2 Released With New Vulkan Extensions, New Shader Cache

Mesa 24.2 is out today as stable for this quarterly feature release to these open-source OpenGL and Vulkan drivers used commonly on Linux systems and other platforms...

https://www.phoronix.com/news/Mesa-24.2-Released

[dimko]

I wonder how this shader cache is going to work with existing Steam shader cache.

[kiffmet]

dimko probably, "fossilize-replay" populates the mesa shader cache before the game is run and then it's all good.

[illwieckz]

Mesa 24.2 in turn is what should be the default graphics driver stack of Ubuntu 24.10 and other upcoming Linux distribution releases.

I hope they will backport that (a fix for a regression affecting bindless texture): https://gitlab.freedesktop.org/mesa/...requests/30338

That fix unfortunately missed the 24.2 release… 😥️

[illwieckz]

I wonder how this shader cache is going to work with existing Steam shader cache.

Mesa already had a shader cache for years, so I guess what changes is that there is a new implementation of it.

Usually each cache works above the below one. If one cache has the requested file, it serves it, but if the file is not available the cache requests the file from the lower cache, etc.

[fulalas]

This is version that comes with the magical 7 lines of code that 'massively improved performance', right? Tested it on Unigine Superposition and didn't see any improvement. Can anyone confirm?

[Lbibass]

This is version that comes with the magical 7 lines of code that 'massively improved performance', right? Tested it on Unigine Superposition and didn't see any improvement. Can anyone confirm?

That massive performance increase was basically for one game. Which he goes over in the blog post.

[smitty3268]

This is version that comes with the magical 7 lines of code that 'massively improved performance', right? Tested it on Unigine Superposition and didn't see any improvement. Can anyone confirm?

It was to speed up glReadPixel calls, I believe, which isn't exactly something most games are going to use. I think stuff like screenshotting software probably uses it. And i think his blog post was about a video or something. Pretty unlikely Unigine is using it for anything.

[Nille]

It was to speed up glReadPixel calls, I believe, which isn't exactly something most games are going to use.

WoW used it with OpenGL to render the minimap. And as far as i know there where a bunch of workarounds for ATIs buggy ReadPixel function in the fglrx driver. With the decline of OpenGL its less important but still a big thing.

[user1]

Is it now defaulting to Valve's single file shader cache that's already available for a few years, or is it a completely new implementation?
Also, does anyone have a link to the relevant commit / merge request?