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First of all: the problem is not related to C4d plugin since the same render failure I get with standalone.
So I've brought the 2nd rule!

But: I need a general suggestion because could be related to my error on setting up Octane c4d parameters.

The scene is really big (about 2Gb) so let me know if is better to send it by We Transfer on your mail Ahmet.

The failure is related to an out- of-memory on my GPU's (that have 11Gb each).
Seems to be related on a group of 3d people, infact removing that group, the render start.
The group is about 1,5 M polygons, the total on the scene is about 6M polygons.
I've no subdivision applied and no displacements on that group.
The only thing is that are composed by a series of nested MIX materials (about 5 or 6), as atm RederPeople use to do on its 3D people octane version.
If I try to render the group alone and.. it works without problem (except the first time)!!

So, I'm ready to send the scene, for having an help. Or trying some of your suggestions. Let me know.







Win 7 64 bit
32 GB RAM
3x1080ti
378.78
Octane 3.06.2

Hi Luca,
I have not downloaded the scene yet, but reading through the Log output, it seems that geometry is only 2GB, while Textures are up to 8GB.
Is it not possible to load the 3d people with a lower resolution textures, to free up some VRAM, and avoid to use Out-of-core, especially with 11GB of VRAM?
ciao beppe

Hi Beppe!

I'll surely investigate on your point, but I wish also to know:


- I have enabled the out-of core feature, with 6GB of amount, shouln't have I overtake the problem?
Or you suggest that the problem could be that I could overcome also my total PC RAM on board (that is "only" 32 GB?)

Hi Luca,
since the textures in scene ar up to 8GB, 6GB of Out-of-core are not enough.
Try with 9/10GB to see of it’s enough, and if your system can handle the reduction.
Do you mind to post the log without the 3d people in scene?
ciao beppe

Thank you very much Beppe.

Raising the Out-of-core amount to 12GB solve the problem.
(here in any case the log without 3d people)
It's important for me to know if I have understood well Octane memory management, so please can you confirm that:

1) the VRam amount for each GPU is used for Textures and Polygons (sorry my rough terms)

2) if total Texture memory amount exceed GPU VRam capability, Out-of-core parameters get involved. But oppositely to my believe, out of core amount used are not added to GPU GB Vram amount, if out of core is enabled only PC RAM is used, correct?

3) other crucial aspect for avoid a Render Failure is the total amount of Polygons. The exact number used in a scene is not only the real polygons present in the scene, the total is composed also by extra polygons generated by Subdividers and Displacement node, correct?
Here I'm a little bit confused: GPU Vram is also used in this phase? So we can say that, for example, a 70 M total polygons scene could render on a 11GB GPU but not in a 8 GB one, correct? And here the out of core parameter is not used, right?

So thank you again for support, sorry for posting here in Bug section (move the post in another place could be better), but at the end for me (and other users I hope) is crucial to know how avoid render error on big scenes.

Luca

Hi Luca,
glad to know that increasing the Out-of-core amount has solved the issue, and thanks for sharing the log without 3d people.
So they are costing ~400MB of geometry, and up to 3GB of textures

About VRAM memory and Out-of core, roughly, in VRAM geometry and textures are the elements that cost more.
Currently geometry has a limit of ~79 millions triangles, ~40 millions poly, equals to 8.5GB of VRAM, and cannot be moved into system RAM, without losing too much speed.
On the other side, textures do not have a limit, and can be moved into system RAM, thanks to the Out-of-core option.
There is a performance drop, about 10/20% depending on scenes, but in this way, you can excede the amount of VRAM of your GPUs , leaving roughly almost of VRAM for geometry only.
Unfortunately not all VRAM is always completely available, Win 10, monitors connected to GPUs, and other applications, can reduce the available VRAM amount.
Note that in c4d Project information panel (Ctrl+I), you can have an idea of the polygon count in both LV and PV: On the log, it is possible to have all these info, and correct the geometry subdivision, or textures resolution, depending on the scene.
Please, let me know if something is still not clear.
Happy GPU Rendering,
ciao beppe