Refresh VRAM?
Hi. I have always this thing that is truly annoying. I work in a scene, use a Gen9 in normal scene (interior or exterior) and everything works fine. If I render it, it uses GPU (Nvidia with 8Gb VRAM) and it's very fast. If I do changes in the scene like changing materials, pose, adding a prop, it's more likely that VRAM will get full and if I try to render, it won't render with GPU and move to the slowest CPU. Sometimes it just needs a single change to stop using GPU. What I have to do, is saving, closing the scene, close DAZ, and then re open and then it will render with GPU. I guess DAZ is using VRAM to store every change for the undo history, (which would be very inefficient if it could use RAM or SSD). Anyway, I was wondering if there's a way to refresh all VRAM so that it uses GPU when rendering and I don't have to close scene and DAZ, and lose 5-10 min (sometimes more).
I have a Windows 11 lap, i9 12th gen processor, 40Gb Ram and 3070 ti with 8 Gb VRAM.
Thanks!
Comments
VRAM doesn't store undo changes.
Your 3070Ti has about 4GB's of VRAM available for Iray rendering.
One G8 figure with clothing and hair usually takes about 800MB-1.5GB's of VRAM, G9 takes more
If you use Iray preview, VRAM is caching scene related stuff for later use (=Do not use Iray preview)
When doing a normal render, scene related stuff is left in VRAM for later use - This is not the same stuff as the preview cache, because the stuff in the preview cache is lower quality
Undo stack in DS is stored in RAM rather than VRAM.
If one doesn't have abundant available phisycal VRAM, monitoring VRAM assumption with GPU-Z is always a good practice.
Thanks for your comment. Well, if VRAM doesn't store undo changes, then why GPU rendering turns unavailable after making changes in the scene (materials, light, pose, etc..), but becomes available after closing the scene and restarting DAZ? Then DAZ is storing the scene cache related stuff of every minor change you make, stocking the data as if it was storing Undo... It's easy to say "Don't use Iray Preview..." but then how would I be able to check if the changes I made (new light, tunning lighting, changing materials, camera view, positions etc...) work? I turn it off if I'm changing pose, but with materials and lightning it would be absurd to turn it off (It would be like blind-mode...), and worse if after all these changes, GPU rendering would be disabled because of stocking all previous data, and then would have to wait 20 min for the rendering to check a single minor change, or close the file and wait 5 for it to restart and load scene...
I understand that you will not like my responce but G9 and GPU with 8 GB VRAM is bad combination. It's like having a raft and wanting to cross the Atlantic Ocean. Yes it is possible but a big pain. If I am correct, G9 uses 8k textures (I am not sure as I stay by G8). G8 uses 4k textures. Because texture is 2D, 8k needs 4 times more VRAM than 4k.
Yes, DAZ lefts lot of stuff in VRAM so you need to restart DAZ to release it. Luckily, DAZ improved loading of Genesis significantly. If you need to stop DAZ fast, kill the process in task manager.
Some tips that may help you:
If I am in VRAM constrain I use this https://www.daz3d.com/scene-optimizer
You can do it manually, but it is so much easier.
The only G9 texture that is 8k is the details normal map.
But unless you are up very close, I would say you can reduce textures, probably to 1k textures.
Below is 3 images with Victoria 9 HD, using a high compression limit of 4k, and medium at 2k.
First is out of the box
Second is with textures reduced by 50%, e.g. from 4k to 2k
Third is with textures reduced to 25%, e.g. from 4k to 1k.
I have an RTX 3060 12GB and I never use Iray preview, the texture shaded view gives me good enough idea of what the scene looks like and when I want to see how it looks rendered, it doesn't take but a minute to get a render that tells me what I need to know.
The 8GB GPU is about the minimum for the latest versions of DS when using relatively recent assets and it is limiting what you can do in DS.