Maximum Out of Core Memory

[Teddi]

Hi,

I've tried searching about this topic but couldn't find anything that answers this question:

What's the maximum amount of Out of Core memory you can use in Octane C4D?

I ask because I need to merge two scenes and both scenes are nearly over the Vram limit on my cards (8gb available of 11gb total, Windows 10 issue apparently).

So merged together I'll need about 16gb of memory.

I tried merging them but I went over my Vram and used all of my system RAM and my system crashed.

If I doubled my system RAM from 32gb to 64gb I'd have enough RAM to cope with the scene, but would Octane be able to deal with it?

I know it slows down renders by 10-20% but I'm willing to deal with that if I can get all of the textures loaded up.

Cheers.

[Terryvfx]

As I understand Out of Core will help you offload the textures to the RAM but the Geo will always need to stay in the Vram so if the Geo in your scene is more than your Vram budge it wont render, and I don't think there is a maximun in the amount of memory it can take just that condition with the textures, maybe you can also explore alternative ways to make your scene lither like using instances, there is a bunch of techniques for this.

[aoktar]

As I understand Out of Core will help you offload the textures to the RAM but the Geo will always need to stay in the Vram so if the Geo in your scene is more than your Vram budge it wont render, and I don't think there is a maximun in the amount of memory it can take just that condition with the textures, maybe you can also explore alternative ways to make your scene lither like using instances, there is a bunch of techniques for this.

It's correct! See diagram below.
https://docs.otoy.com/Cinema4DH/C4DPlug ... erCore.htm

[Teddi]

Thanks both.

My scene is within the geometry limits of my cards, it's definitely the textures that are crashing my system when I try to merge two heavy scenes into one.

I've got more RAM for my main machine arriving tomorrow so will see how copes.

Also my slave machine keeps crashing when trying to render a complex scene.

It's an old i7 950 machine with only 12gb of RAM and two 1080s, my master machine has two 1080ti's and I *think* my slave machine is trying to use Out of Core memory to make up for the difference in Vram between the two models of GPU, and it's running out of system RAM and crashing (tends to freeze, or just show a black screen and I have to reboot).

Considering getting another 12gb of RAM for the slave machine, will that help deal with the lack of Vram on the 1080s?

I don't normally work with such heavy scenes but this is a portfolio project so I'm pushing the boat out, so to speak.

Also the tip about parallel samples and tiles in the documentation is useful, I wasn't really aware of what those settings did, I'll try turning them down on heavy scenes.

[Terryvfx]

If would help if that's the problem you could first try to unload some of the textures and see if that's what's making your slave crash.

I will just leave here some notes in case you missed any it could help you out with memory management.
- Using more than 8bits maps for anything other than displacement rarely affect the final image (16bits images are REALLY heavy on memory)
- Always load your "control" textures on float, you know bump/roughness/etc.
- HDRs weight a TON in memory so if you are using a pretty big one but don't need the extra resolution you can always scale it down.
- Use and abuse render instances.
- Use procedural textures when possible.

I know you didn't ask for this notes but just in case.

[Teddi]

Thanks Terry.

I've got the scene working fine now with 64gb of RAM.

I'm using about 2gb of Out of Core memory on my master machine.

Not bothered running the slave on this scene as I'm pretty certain it'll crash due to lack of Vram (1080 vs 1080ti) and lack of system RAM (12gb).

Think I'll get another 12gb of RAM for that machine as it's a fairly cheap upgrade.

Still not sure exactly how Out of Core memory is handled in network rendering though.

ATM my current assumption is that the slave will use its local Out of Core memory to match the Vram of the larger capacity cards on the master machine. And the master machine uses its Out of Core memory as a texture memory overflow for all machines on the network.

Not sure if that's correct though.

[bepeg4d]

Hi Teddi,
please, have a look at this other discussion about Out of Core on Slave nodes:
viewtopic.php?f=23&t=60512
ciao beppe