MtoA 4.1.0 Parts of Textures missing on GPU

[lennart.oberscheidt]

Hey,

I already have another Thread open at the moment (RTX 3090 memory errors) but while trying out Arnold 4.1.0 to circumvent the issues I had with that card, I noticed a more serious issue then the little annoying GPU not doing exactly what it should 😉

When using UDIM tiles (well not sure if there's any connection, but they are UDIMs in this case) in MtoA 4.1.0 parts of textures will randomly be missing. This will not happen in other versions of arnold. This happens in a mix shader (texture input is fed into the mix of the…mix). The part might render on some frames and not on others, when running the IPR they might appear or not appear. This seems to happen on RTX 3090s as well as a 1080.

Here are the Screenshots. The "9" (Which is on the same UDIM tile as other the parts of the tail number of the plane) will randomly just go missing. Also other parts of the texture.

I can provide a file (full project) for investigation tomorrow if you want to have it. Sorry for starting two threads, but it seems to be one of those days where issues just magically appear out of thin air 😉

Lennart

[lennart.oberscheidt]

Maybe some more information: The "9" might reappear after restarting the IPR. When rendering a sequence it might be there for some frames, then it's gone for one, then reappear. At the moment, no other computers are accessing the file location, no other arnold versions or anything really is grabbing that texture at the same time. The texture is stored on a network drive. But as I said, that thing renders perfectly without issues on other arnold versions, even on 1000+ frame long sequences (turnaround, some shots etc.)

[lennart.oberscheidt]

And…that will also randomly happen apparently (basically, everything else goes missing 😉 :

Well…back to 4.0.4.1 😉

[lennart.oberscheidt]

And maybe just another additional observation: The texture will be there for maybe the first 1-2-3 samples passes, and then just vanish after a certain sample level and be gone forever…

[thiago.ize · Accepted solution]

I wonder if this could be due to the new sparse textures. You can try disabling it by setting options.gpu_sparse_textures to 0.

[lennart.oberscheidt]

I'll try that immediately.

[lennart.oberscheidt]

Safari wont let me answer under your comment Thiago, so here's my reply:

Thank you, that worked, at least in 10-12 IPR refreshes now. I am correct in assuming that the option would be input as "gpu_sparse_textures 0" (without quotes) for IPR in the Options field in the Render Globals "Diagnostics" tab? (Never had to set options from the interface before). Well Arnold seems to have build some caches again since it took a while after that, so I assume that kinda worked since it now stays where it is 😉

Would you like to receive the file for testing purposes? (It's really not that much of a very complicated shader setup) If yes, where to?

Thanks again,

Lennart

[thiago.ize]

Does this fail with the latest nvidia driver (457.30 I believe)? NVIDIA has been fixing a bunch of these texturing bugs, so it's always worth testing the latest driver in case it's already fixed.

[lennart.oberscheidt]

Unfortunately, yes, this is on 457.30 (updated one machine based on your recommendation in the other thread). It's happening on the 456 and 457.30