GTX 980 TI (gb VRAM) often can't fit even 2 characters into VRAM. Is this because of Optix Prime?
hlln334
Posts: 30
I don't know if I'm doing something wrong here or what, but it's often the case that even two characters (and in some cases even one, with a lot of clothing) will either cause the render to default to CPU-only-mode or push the VRAM being used so high that, according to MSI Afterburner, I'm at 5.6, 5.7gb vram.
This is constent, too, meaning that it's not a matter of restarting or closing/reopening the program (although I have to do that sometimes to get the GPU to work again)
What I mean when I use the term "constant" is that for any situation in which 2 or 1 characters are unable to fit into VRAM, the situation is unaffected by restarting the PC or Daz3d.
In other words, even if I recreate the scene from SCRATCH, it'll be the casy that loading THAT model, with THAT skin, in THAT clothing, with Optix Prime enabled, will cause the VRAM issues to happen immediately.
Is this normal? Or is it just me. It's also very peculiar what causes it to happen. Sometimes I can fit up to 5 characters and lots of models into a scene with Optix enabled no problems.
Other times, even just a single prop like the bed from the Comfort Bedroom set all by itself won't fit into VRAM with Optix Prime Acceleration set to enabled.
(Also, resolution does not seem to affect this, either).
Oh, right, and I'm using the latest build of Daz3d (or I believe it's the latest. 4.9.2.xx)
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Oh, right, and one more thing I forgot to say. I tried loading a blank scene with literally nothing in it. (Absolutely, 100% nothing. Completely blank. Nothing to render at all so that it renders to 100% pretty much instantly. Just press the "new scene" button then click Render)
Rendering literally nothing, I often see up to 2, 2.5gb of VRAM usage.
DS iray seems to use all it can, do not tick CPU at all.
and I have Octane render and a 980ti and that does not do that.
so its DAZ iray thing
This seems rather odd, but some clotiing items do take more VRAM due to hires textures and the number of textures used. Some characters also teke more VRAM than others, and HD characters with increased subd levels will also consume more VRAM. It might be helpful if you could add a list of the items used.
I was able to render the scene below on a 970m with 6Gb of ram, so two figures "should" easily fit in 6Gb.
See this image in my gallery
Do you have incomplete render windows open? That will do it.
As well, try looking at what background applications you have open.
Another big plus for Octane it that it can use out of core memory (system RAM) for texture data, freeing up more space for geometry data on the GPU. I've had 8 fully clothed Genesis and Genesis 2 figures (with hair) in an Octane render scene, with a LOT of room to spare.
So - is your 980 TI also running your monior(s)? This can chew up 300 MB to over a GB, depending on what else you're running and what shows on the screen(s). I have a 980 TI and can routinely get a Stonemason set and two to four Genesis 3 characters morphed and clothed while using less than 5 GB of Vram. My monitors run off a gt 740.
Wow, beautiful render! Love the Depth of Field!
But to answer your question, I'm using FWSA Dayna HD (it's for Eva 7)
Any scene I put her into, it's bound to take 5+gb of VRAM regardless of complexity, but that tends to usually be with Optix Prime enabled.
Yeah, should I look into getting a dirt cheap card just for my monitor? That's not a bad idea, actually. But usually, before I press the render button, between my desktop (which I tested, idle at the desktop it uses ~240mb of vram) + whatever daz3d uses, I'm down about 800mb before I press render.
I wonder if there's a way of minimizing how much gets used just on Daz (the viewport I mean). I've tried changing to wireframe with little difference.
What is Optix Prime supposed to do?
It makes you render things MUCH faster (like, I've sometimes had as much as a third or even a half of the render time shaved off) but, in my case, it's eating into my VRAM. Sometimes by as much as 1.5gb VRAM.
It's in the advanced tab in the render pane (the thing I'm talking about) you know where you choose CPU, GPU, etc?
There's a setting there called "Optix Prime Acceleration."
Thanks!
I should have added that the render was done with Optix enabled, and the same GPU was also running my maonitor. I don't have FWSA Dayana, so maybe someone else will chime in.
I have Dayna & with hair, clothes she took oround 3.6 GB (Optix enabled) - I only have 4GB so she is alone in the test
Okay so I guess that's about right then. Add a second character, and you shoot up to that 5gb+ limit.
Well, I guess at the very least I can say that she's certainly worth it. By that, I mean that the 3.6 really buys you one hell of a good-looking model. But if you're also getting around ~3.6gb with just one character (that one), then it would explain why the VRAM is so high for me as well lol.
Check to see if the item has the SubD Dispalcement level on one or moer of its surfaces set high - I had an item the other day set at 5 (only on one surface, but the highest setting applies to the whole mdoel) and another at 4 - both caused the 4GB video card to drop out. (5 multiplies the polygon count by 1,000, 4 by 250 - both models ended up with tens of millions of polygons in the GPU, in addition to the rest of the scene).
You could always reduce the texture sizes or remove the normal map to reduce load if you are not doing close ups or super large renders of her as textures seem to take up most of the vram
I thought that setting SubD Displacement Level on a surface affected only that surface. I thought that is why it was there in the surface settings - to affect only one surface. I thought the Render SubD Level (Minimum) in the Parameters pane General section was the only thing that affected the whole model. Have I misinterpreted this the whole time, Richard?
Another thing to check is the Medium and High compression thresholds in the Render Settings, Advanced tab. Those will affect how much your textures will be compressed. Try lowering those values and see if that makes a difference. If you see texture artifacts in the render, you probably went to low.
That actually helped me on a set of clothing I had problems with & could not figure out why as no matter what I did the vram usage was high :)
Dayna has no SubD though
That is what we were originmally told, and what the initial 4.8 betas did I think, but that was not the correct behaviour and in fact the whole model is divided to the maximum of the Render SubD level and the SubD levels on the surfaces (the Render SubD also smooths the mesh, the surface setting dividies without changing the shape, as I understand it).
Oh, my goodness!! Thank you for clarifying the way it really works now.
I was already convinced that displacement in Iray was pretty much unusable. Now I am even more convinced. I wish vendors would quit using 3Delight displacement maps with tiny details in their Iray materials. This is one of my (many) pet peeves about "Iray" materials.
DOH! Whelp, that explains everything. This should literally be on a freaking tooltip! Thank you so much for this!
It also helps explain why the Iray Memory Assistant gets the estimates so wrong sometimes. It doesn't take surface SubD into account at all, as I understand it.
It would be useful to have a script that would reset all displacement related settings on all Iray Uber surfaces of all selected objects. Then we could select all objects in the Scene pane and wipe out the displacement stuff that doesn't render well and only uses up our GPU ram.
You were right, Richard. Upon checking, the model's hair I used had a SubD Displacement (in surfaces, not parameters) of 4. I lowered that to 1 and it shaved 900mb of VRAM. Sheesh!
Yup. I bought that cool little script and have been scratching my head wondering why it says there's 2gb VRAM left but I'm COMPLETELY out. Now I understand why my 6gb couldn't take me very far LOL. You live and you learn!
Okay, between clothing, hair, and a bookshelf, I've cut that 5.4gb VRAM down to 3.2. Thanks again, Richard!
Oh wow... this now solves the mystery I've had as to why some hairs render 4 times slower.
There might be a better way, but it would be easy to make a shader preset that set displacement level to zero. then you'd just need to select everything and apply it. Just pick any material that has the displacement strength set to 0 save as> shader preset than set it so only displacement level is checked (or check all the displacement settings to make a version that clears out the maps too).
To make things even easier you can find it in your content library and right click > create custom action and therell be a shortcut for it up in the top menu. I have a bunch of useful shader presets up there like the iray default and my skin and hair settings.
I've seen clothing items with nearly half a million polygons on the base mesh. It's truly amazing sometimes what you find. Hair can be notoriously bad too for polygon count. Also, video ram won't always be freed up if DAZ Studio crashes (and in some cases when you simply close DAZ Studio). This means that next time you run it, you have less video ram to work with. It's rare, but it does happen and it's annoying because small scenes render, but normal scenes that you had no problem rendering before switches to CPU mode. If anyone runs into this kind of symptom, this could be what it is. The only way to free the memory is to reboot.