Justin Keil

brians
some random thoughts:

brians
In fact the final render readout on a single layer with these trees is 50 gb of vram for a single frame

sorry, how did you come up with this 50gb number? Is that something you got from XPU? Or some other package? XPU only loads the data it needs onto GPU (demand-loading), so it might make use of less GPU ram than you initially think.

XPU will go out-of-core for textures, although the GPU will most likely run very slowly in this state.

On Windows, GPU memory will spill over to CPU memory (called "Shared memory") and seems to be still rather performant in this case. Please note this will not work on Linux, or if you have 2 GPUs.
https://nvidia.custhelp.com/app/answers/detail/a_id/5490/~/system-memory-fallback-for-stable-diffusion [nvidia.custhelp.com]

Hewy Brian,
Apologies for the delayed response. I have since updated to houdini 20. Now the readout in the clone is not indicating an optix of zero..... It is still utilizing the gpus (at least one of them), even with the load memory peaking at 39 GBs.
I've attached a pick. thank you for your insights, and helping me resolve some of my own ignorance.

Brian if you don’t mind me asking a second related question. In a two gpu system with one powerful gpu (4090) and one weaker gpu (4060) Is it possible to configure Houdini so that it is using the 4090 exclusively for karma render tasks, but the 4060 for everything else (viewport navigation, etc)?
Alternatively I could force Houdini to only use the 4090 in the environment file, but then I presume some of the vram from the 4090 would still be getting consumed by non karma related tasks…..just trying to think of ways to be as optimized as possible!

Helpful Brian thanks. The readout on memory was coming from the render gallery.
I set it up using this here-

https://m.youtube.com/watch?v=q7kQh53v6Fs. [m.youtube.com]

Let me double check myself on the exact numbers though and get you a screenshot tomorrow. I have to make sure that the scene memory consumption is actually the same read as the vram consumption.
Give me a beat!