There is not a lot of documentation or info about this feature, but we have formally asked NVidia to give us more and they're working on it. One thing we know is that it doesn't work if there are two GPUs in the machine.
you can disable the feature by setting the "CUDA system fallback policy" to "Prefer No Sysmem fallback" in the NVidia control panel. Once you have done that then windows and linux should behave the same.
well i just test a large scene with 2 gpu and karma xpu in windows working perfectly , both gpu doesn't failing but in ubuntu gpu it failed easly again.
soo i'm guessing thats this feature work also with 2 gpu? if not then I have no idea why its happening (and i dont have problem with this situation because its not failing and the rendering is faster but i want to know out of curiosity why its happening). by the way with this feature even if the driver send data to the CPU memory the rendering in xpu in windows its always faster then in linux when the gpu failing in linux.
i just try to test kamra xpu and i'm notice that if i render the same scene (large scene) in linux and windows It behaves differently
in windows both cpu & gpu working and in linux the gpu failed
i test it in a few scenes (also very large scene) and all of them are the same (in linux it failing and in windows it working) (I guess it will be like that for everyone)
why in linux its failing and in windows not? its the same vram . and if its the nvidia windows drivers why its happening?
if i have "principled Shader" and "materialx" connected to "collect" node how do i force karma CPU to use "principled Shader" when both "principled Shader" and "materialx" connected to "collect"? because its always using materialx
tbay312 Thanks everyone for the feedback - There's a lot of ground to cover with this kind of video, so getting lots of smart eyes / minds on it is always helpful. The final video can be found here:
Cheers,
- Tyler
i have a few question as you know the main use of houdini its in large/huge vfx scenes thats a lot of studios are doing soo so why not take their comments in addition to your students?
Also after i mention that alot of studios using houdini for large vfx scenes , you compare redshift against karma with a simple scene and you forgot big big issue soo what happen if you have only 16/20/24gb vram card and you have large scene? In this situation do you still preferred to use redshift? and how redshift handle large scene compare to karma xpu/cpu or arnold?
and one more question and i guess alot of people want to ask you , can you make redshift vs arnold review?
nice comparison but their is a subjects that i dont understand like features "non usd" or "rs proxy" or "material x" ..... thats not related to the comparison because xpu will never have rs proxies and its always will be for usd (i think)and also karma XPU was built with material x support from the ground-up soo no need to mention it.
and you compare "hybrid rendering" soo how can you compare karma XPU that was built from the ground-up for multi-devices to redshift ? its a two different worlds
but isn't the comparison too early? because XPU is relative new
habernir but i want to control the number of repeat in the u direction (i want for example do make 2,3 or 4 lines....)
There is no built in mechanism for this. You'll have to get out the math and do it yourself. The clamp node can be used to clamp the scaled u and v values to the desire maximum
thanks. i already know about clamp but i forgot that there is mtlx clamp and thats solved my problem in mtlx
Enivob Use a mtlxTiledImage node and increase the Realworldsize to introduce more copies.
thanks for your answer but the mtlxTiledImage its just tiled rate in uv direction and the Realworldsize just control the size of the single square ( am i wrong?)
this is the result
i want to control the number of repetition in the u direction
in mtlxImage i make U Address Mode: periodic V Address Mode:Constant
and the result its repeating along the u direction like this
but i want to control the number of repeat in the u direction (i want for example do make 2,3 or 4 lines....)