Render W/ Viewport Subdivision = NOT Multi-Threaded

[whtnoise]

Running into an issue where it seems like anytime I render with the viewport subdivision global on, V-Ray won't use more than one thread to render??? CPU usage hovers around 15% and the render itself crawls, even with Default Subdivision set to ~4.

As soon as I turn it of the CPU's are completely pegged and the render flies - part of that seems obvious, not using the VP sudiv global, but for the whole process to not be multi-threaded, does that make sense?

Edit: Can't say for certain this is the case - but in the scene that I'm working in, it definitely seems like it is. Testing on something simple doesn't produce the same effect...

Is there any instance where something like this could possibly happen?

[Metzger]

Do you have large textures and GI turned on as well? Have you exported your geo as an OBJ, then imported it back into maya? Make sure you check your model for any strangeness like bad normals and un-merged vertices.

[vlado]

Make sure your "dynamic memory limit" setting is high enough; the default is 400 MB which is way too low for most scenes. There are also lots of improvements in that regard in the latest nightly builds.

Best regards,
Vlado

[whtnoise]

No large textures, GI is on, dynamic memory limit has been between 6000-8000. Going to try upping it some more to see what happens... Would try exporting geo, but there's quite a bit of animated tube-type geo and object wrapping going on.

Wasn't trying to be an alarmist with the post title, just came across as extremely odd... Can't imagine it's anything else but a memory issue.

Vlado, I'm assuming I should just email you for access to the nightly builds?

Thanks dudes.

[vlado]

Yes, you can email me to vlado@chaosgroup.com If you still have issues, it might be useful if we could take a look at the scene itself.

Best regards,
Vlado

[Metzger]

Animated tube animation? So is the vertex count changing per frame on the object? Are you getting Geometric normal error in you script log? You might want to remove the subd and just add a maya smooth to the object. One other thing I like to do is keep animation files totally separate from render files. Meaning you will want to bake out your animation so you can attach deformations to the original model. I would make two groups in your maya scene. Deformed Geo, and non deformable geo.

Use geo cache.

I like to use FBX as a container for geo cache and keyframed non deformable geo. The nice thing is that I can have the original model in my light file with no animation history. Then I go to import the FBX data and choose import and replace. It will only attach geo_cache, and keyframed curves to the light file leaving you with a really nice scene that translates perfectly into vray.

[whtnoise]

It's a paint fx stroke tube thing. I'm coming from max, jumping into Maya pipeline and trying to work out V-Ray kinks. Vertex count is changing from frame-to-frame, which V-Ray gives warnings for, something to the effect of:

V-Ray warning: Mesh "sh_0040_Anim_v07:cloth_rig:floPly550Shape" has changing number of vertices (14220 expected, 14228 actual).

Was weighing smoothing versus VP subds, just too many objects to be worth it at this point (wrapping in a couple days, just want to get the render out)

Our pipeline here is similar to what you're talking about, layout is referenced into animation, and animation into lighting. Due to how much this shot in particular has changed, revisions were being made right up until render, and we never worked out a good solution for baking it out. Ah well...

FBX as a container sounds interesting, might try that out in the future...

Metzger - Just checked out your profile, was at Method NY for a short bit late last year, good folk over there Thanks for all the ideas!

[Metzger]

I would remove the SubD, add the maya smooth and then do an create vray proxy with animation... Yeah, most render issues come from animation history. I sound like a fascist dictator over here when it comes to scene organization just for reasons like this. 90 percent of all render issues come from trying to render animated files.

Very cool that you worked at Method NY. I hope you had a chance to work with Pink while he was there.