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Color management difference when using multiple and different GPUs together
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Description

System Information
Windows 10 64-bits
Intel Core i7-2600K
CUDA Rendering with GTX 560 Ti (sm_21) and GTX 780 (sm_35)

Blender Version
Broken: latest builds from Blender Buildbot, GraphicAll.org, and my own compiled builds (all of them 2.78.5)
Worked: official 2.78.1 release

Short description of error

I tried to use my older GTX 560 Ti with my GTX 780 to get faster renders, but I encountered this strange behavior when combining them: Picture here, Another example
I thought that the different CUDA kernels (sm_35 and sm_21) were the cause of this weird tiling effect. However, this does not happen when I use only one GPU at a time (and I get exactly the same results for both GPUs, no problem).

May have something to do with color management when using multiple GPUs, the problem disappears when I mute the Image texture node here:

Original post @Blender StackExchange

Event Timeline

Maxime Michel (maximemichel) renamed this task from Hue difference when using multiple and different GPUs together to Color management difference when using multiple and different GPUs together.Jul 18 2017, 2:12 PM
Maxime Michel (maximemichel) created this task.

@Stefan Werner (swerner), I'm guessing this is due to rBec25060a05e3: Unlimited number of textures for Cycles, mixing cases with bindless texture support and not. Not sure if there's a good way to make this work.

Brecht Van Lommel (brecht) lowered the priority of this task from 90 to Normal.Jul 18 2017, 2:40 PM

The attached scene is missing its textures. Can you please pack them and upload it again?

@Brecht Van Lommel (brecht) You're probably right. I think it needs to use the same texture IDs for all CUDA architectures and then map back to SM_2x on the kernel side. I'll go dig out my GTX 460...

Sorry I forgot to pack the textures indeed, should be okay now:

@Maxime Michel (maximemichel) if you could please verify that this is fixed with the upcoming automated builds.

I can't get the kernel to be compiled :

ptxas fatal   : More than 128 textures used in entry function 'kernel_cuda_branched_path_trace'

Full log here

I can't get the kernel to be compiled :

ptxas fatal   : More than 128 textures used in entry function 'kernel_cuda_branched_path_trace'

Same here. Win10 x64

Thanks, will take another look. Give me a couple of minutes.

Will test your new commit ASAP ;)

Should be working in c1ca3c8.

Seems to be working fine now! Thanks a lot ;)