I'm having pretty serious render issues at work and hopefully one of you may have run into this before and know whats up! It's plagued me at work for a couple months, seemingly increasing in frequency too.
Our scenes consist of really high poly environments, natural stone, wood, all of it sculpted and decimated in zbrush. We don't really optimize mesh density past a point since we use them modular wise in different situations.. so they're pretty dense. Some scenes have foliage, but this issue has come up in scenes with none, so I think this is a non issue.
As far as shaders go, we use almost exclusively procedural shader networks (node counts range from 5-35 depending on complexity). We do use file textures here and there, mostly for leaves and organic stuff, but again, this issue has happened on scenes with no file textures as well.
Also, we use mia_x 100% of the time. lately, I've been doing mia_x passes. More on this in a sec
typical scene info:
tri's: 10-36,000,000 (20-36 million)
contrast ratio: .08
render as layered exr
32 bit rgba output
render passes:diffuse, specular, reflective, refractive, indirect, shadow, depth
Here's my issue:
When I render, (and this seems to only happen when I have render passes associated with the beauty render layer) mental ray gets through the final gather just fine.
however, as soon as it finishes, and moves onto actually rendering the image, it makes it a random percentage of the way through, and just quits. output from the window just tells me there was a fatal error, and it is attempting to save, and then..... the render just keeps on going until it reaches 99.9% and it never actually saves the render.
funny thing is, I can turn down the adaptive sampling to 1/-1, and it sometimes makes it through the render. or it crashes, closer towards the end... This is my problem, pretty much. I need to output passes, but I've no idea what to do.
Things I've tried to no avail:
plenty o ram, usually only reach 7-9 out of my 24, and I'm running maya 2013 x64 on windows 7 x64
no file textures are over 1024, they are all sourced correctly and working. targas, tiffs, png's, etc.
checking "allocate on heap" in options tab in render settings. (seems like this might get it further, but hard to tell.)
I've tried the "divide and conquer" route. one half of objects renders and finishes fine. the other half finishes fine too. both combined.... not so much.
I suspect, that somehow, something, is overflowing data wise, but thats as far as my suspicions go.
I would be ETERNALLY GRATEFUL if anyone has any ideas to try, or even knows exactly whats going on.
Thanks for tuning in to my rant!