Rendering extremely slow

Camthaleon

I have a scene with two characters, male and female. I'm using Daz 4.9

Male has simple short hair not moving, an old greek-like cloth instead of pants, no shirt, has wings. 

Female also has a similar cloth just different color, hair, no shirt.

Animation is 450 frames. I simulated the wind for her hair and cloth. Pretty basic stuff, nothing extreme.

Render time for 1 frame is about 2 hours. Why?

Render Settings, I'm using default iRay, the only thing I changed is render quality which is set to 1.87 I think. It's rendering in 1920x1080. I know pretty big... In Advanced settings I have both CPU and GPU checked, if I do just GPU I get an instant black frame. I read that it's a memory issue. My card is Nvidia Gtx 1070 ftw hybrid gaming 8gb. I just got another one to put in SLI and share the workload.

Other renders: OpenGL gives a frame instantly 3Delight is quite slow but not as slow as iRay. Just doesn't look as good... or photorealistic as it's called.

Is there anything I'm setting up wrong? Anyone else has uber slow render times?

Richard Haseltine

SLI is not supported by Iray, so make sure you disable it for DS. It sounds as if the GPU is not being used so adding a second won't help - it wold be a good idea to look at the log (Help>Troubleshooting>View Log File) to see what is happening. hair can slow the render down, and increase memory use, depending on how it is made. How are you applying wind to the hair - have you added a dForce modifier? That shouldn't diectly affect the render process, which just gets the current state of the geometry, but it may be using and not fully freeing some memory if you are simulating in the same session. Do you have GPU-Z or similar to check how much memory is being used before and during the render?

Camthaleon

Thanks, yep I looked through the log file just now and this really stands out:

WARNING: dzneuraymgr.cpp(261): Iray WARNING - module:category(IRAY:RENDER):   1.0   IRAY   rend warn : GPU 1 (GeForce GTX 1070) with CUDA compute capability 6.1 cannot be used by iray.
WARNING: dzneuraymgr.cpp(261): Iray WARNING - module:category(IRAY:RENDER):   1.0   IRAY   rend warn : There is no GPU available to the iray renderer.

The card is not supported by iray?

The hair is animated just using keyframes and then minor adjustments here and there. But no dforce, I think it's not even available on 4.9, only available in later versions. 

Yes I have GPU-Z, right now it says I'm using 2200mb I have quite a few things open which I close for renders, firefox, chrome etc... 

Richard Haseltine

You may need to update DS - I think later builds of 4.9 had a version of Iray that supported Pascal cards, but I can't recall thee xact point. Check your version - Help>About Daz Studio. Also, even if you have an updated version of DS you will also need a sufficiently current driver version for Pascal support in Iray.

Camthaleon

Yes you are correct, I just found a thread regarding the gtx 1070 specifically. It still says I'm lacking VRAM. Did the purge (script), hid away some objects outside of frame and still not enough :/ In fact even with a blank scene it says I'm missing 200mb vram or so. 

But I did a test render and it still runs the gpu, so go wonder :) It's MUCH faster than using the CPU and probably saved me from doing a full rig upgrade at least for the time being.

I upgraded to the 4.9.4 version of Daz.