Arnold GPU rendering issue

jugobono

I'm experiencing an issue with Arnold GPU rendering in Maya. When I render a scene it seems like Arnold is making a very low usage of the GPU ( between 1% and 4%). This is what the task manager shows so as GPU-Z. Pre-populating the GPU cache does not give different results. Anyone having the same issue?

oglu

have you set the arnold log to debug.?
what does it say?

gnoop

Windows has pretty weird GPU usage graph.  To see what's actually happening you sometimes need to select Compute_0 or Compute_1 from a header drop down list in task manager.

But anyway  don't expect GPU renderer to be same interactive as CPU one on super big scenes.   The complete time could be much quicker still all the GPU renderes have so called "first pixel" issue.     At first GPU render would show you just black background for pretty a while during pre-processing stage.  Heavier the scene longer.   And CPU render often starts to show something just right away up to a stage you are having enough visual feedback while GPU is still showing you nothing but black background.

oglu

I agree here with gnoop. GPU renderer are starting slow and if the scene is heavy Arnold GPU in special will freeze your system.

I dont see any GPU renderer beating Redshift 3.0 in the next 12 Month.

Vray Next is to slow. Arnold and Renderman are in Alpha stage.
Even if Autodesk says Arnold GPU is beta. ;D

jugobono

The log shows on the side the value 2807MB. I found the item "peak GPU memory consumed" to be around 850MB (sorry, I've never used the arnold log). I attach the file below.

@gnoop Both Compute_0 and Compute_1 say 0%

oglu

Could you post your system specs please.

jugobono

AMD Ryzen 7 2700X Eight-Core 3.70GHz
64 GB DDR4
Nvidia Geforce RTX 2070

oglu

Is this with every scene?
Could you do a dummy scene with some cubes and some area lights?

jugobono

Already tried and GPU is always on low usage

oglu

if you upload it here i could testrender it on my system.

jugobono

Does not let me upload .mb format. Here's the drive link https://drive.google.com/file/d/1u6KtyjjUqmKxvPt7RwNSca4wkx4Gh9XN/view?usp=sharing

oglu

The scene is a mess. i had to clean it a bit. 
first try without cleaning it crashed my workstation.

I deleted all lights and did a first render with only one Arnold Area light --> only 4% of my GPU working.

Next step was to use the Adaptive Sampling which is the recommended way to render with GPU and it worked like expected.

jugobono

I tried to clean the scene and now it all works fine. Thank you!