Mesa 22.2.0-rc2-1 is out and updating to it solved the issue for good. As far as I'm concerned this report can be closed.
Thanks for the help with troubleshooting.

Either in 22.2.0-rc2 or in rc3. I'm not exactly sure - rc versions comes after a week after each other, and there are 5 of them. Usually they are released at wednesdays.
I think we will have solid confirmation around sunday/monday when patched version land in distributions experimental/unstable repositories. Debian have Mesa watchfile scan set to Sunday.
Gentoo/Arch will have new version the moment it is released.

The bug got patched in Mesa today: https://gitlab.freedesktop.org/mesa/mesa/-/commit/70891edd9728e7dd73115171fdb03622ce6450ba

Unfortunately I must confirm this. I'm not working on 'production' size scenes, yet with more complicated ones I find that I pause Cycles viewport, tweak some shader parameters and unpause the viewport to see the changes. It's not very efficient way of work,

Vertex Paint mode have option to convert vertex weights to color. You can find it in 'Paint' menu in the top bar -> 'Vertex Color from Weight'.

Unfortunately I wasn't able to simplify the scene and in the end I managed to work around this.
If I will have some spare time I will try to investigate this problem.

It looks that this issue is not related to UDIMs. Tests that I've done on the file that I've attached previously:

Thanks for looking into this.

In D13874#395732, @Fynn Grotehans (TheFynn) wrote:

Is there a general "Blender way" for that kind of problems?

It might be worth noting that thumbnail size / directory view in most used file browsers (Windows & Linux) are bound to [Ctrl] + {Mouse scroll].
I'm not against view pie menu in that context, but areas that overlap with generally used software i.e. OS' should be consistent if possible, otherwise it might look like reinventing the wheel.

If you cannot render Laundromat on a GPU you can try with Barbershop.

Why did you recorded 2 CPU renders? This doesn't make sense with the respect of this bugreport.

In T95361#1298437, @MakeMyGame (MakeMyGame) wrote:

If you have a more complicated scene in mind that i could render i would gladly download and try it.

Can you post some more complicated scene example? When we talked I assumed you saw this problem with production scene.
With rendering default cube the rendering times are so short that the GPU graph in Windows task manager cannot pick it up.

Please rename Blender version from 3.0.1 to 3.1.0 in title. This can be confusing, as both are two separate versions - 3.0.1 is stable, and 3.1.0 is in beta now.

Fixed by https://developer.blender.org/rBbdd74e1e9338b18e4f80458f284d0c6a4d100f30
This report can be closed.
Thank you for your work @Jeroen Bakker (jbakker) @Clément Foucault (fclem)

Thank you for explanation.

I might be wrong, but the problem with viewport updates is not related to rendering engine, but how events from node editors (that include geomentry node editor) are managed by depsgraph. EEVEE have the same problem.

This is an issue in Shader Editor since 2.83.
Here's the task: https://developer.blender.org/T76970

This looks similar to the issue with Musgrave Texture T77681