GPU Memory

[galleon27]

Hello, i have a question regarding GPU memory. I have a huge model, 15 million polys, 50 million points. When i try to render it, Octane crashes and i get a CUDA_ERROR_OUT_OF_MEMORY: out of memory. (attached screenshot). So im guessing i don't have enough GPU ram and that is fine, it happens, doesn't really surprise me. The problem is that when i load the model directly in standalone, it works just fine, and the GPU usage is not even close to being full. It was at like 30-40%. So my question is why does that happen? What is the difference? Are there some other factors that i'm not accounting for?

[juanjgon]

The display GPU can have a lot less memory available when Octane is working inside Houdini because Houdini can be used a lot of VRAM for its own OpenGL viewports. Do you have the same problem if you disable the display GPU?

If it is a GPU memory issue, perhaps enabling the out of core feature could help.

Thanks,
-Juanjo

[galleon27]

The display GPU can have a lot less memory available when Octane is working inside Houdini because Houdini can be used a lot of VRAM for its own OpenGL viewports. Do you have the same problem if you disable the display GPU?

If it is a GPU memory issue, perhaps enabling the out of core feature could help.

Thanks,
-Juanjo

I've done some tests, rendering with all combinations of GPUs, only seconday GPU, only display GPU, then both turned on.
My main GPU is 1080ti and my second one is a 1080 so i don't really think its a GPU memory problem since the scene is 3gbs. I had no issues when rendering with a single GPU. The issue arises when i turn both of them on. Every single time i try to render with both of them, the scene loads and starts to render and at some point IPR goes "gray" and it unloads the object. (see attached images)

[juanjgon]

Can you send me this scene to take a look at it here? Meanwhile, perhaps as a workaround, you could try to break this object in two, to have individual objects with less amount of geo information. If this helps, it could point to the origin of the problem. In any case it is really weird that the same doesn't happen in Standalone, if both Standalone and the plugin are the same version.

Thanks,
-Juanjo

[galleon27]

Unfortunately i can't share the model as it is a production model. In the end i just assembled the whole scene in Standalone so its not really a big problem. I'll try and break the object and see if that helps.
And since i can't share this model, i'll try and replicate the issue with a model that i can share.

Thanks.

[galleon27]

Ok so after some more testing i've come to the conclusion that it not an Octane problem. I had to reinstall my system, switched my display gpu from 1080ti to 1080 and now everything works fine. So i guess something in my setup was at fault. Thanks anyway.

[juanjgon]

No problem! I'm glad that the problem has been resolved.

Thanks,
-Juanjo