vray smoothing attr's making renders hang

[SteveMack]

We have a problem in production right now where using vray smoothing attributes to smooth objects at rendertime is causing renders to hang indefinitely... Could be while it's loading textures, can be during prepass, can be during render, sometimes right after it says "starting 8 threads" or whatever.. But render will just hang and take up tons of memory, but not fail directly, so our farm can't recover from it without a user noticing the problem. This is a big problem, we need these shots out. For now we will turn off smoothing and switch to using maya mesh smoothing, but this wasted days of rendertime.

[SteveMack]

I should note that these are very tough scenes for our hardware in some cases, 8 million polys in some cases, 100+ textures, etc.

[aweidenhammer]

This sounds like the same issue over and over again up your dynamic RAM setting in the settings tab. This issue has been discussed. You are better off using meshsmooths for now anyway. Not to sound short, but wasn't this discussed literally in the thread before this one?

[SteveMack]

Maybe it did, I did look around + search and only saw threads about adding the attributes and such. is there a place where the effects of dynamic memory limit are discussed? I see a short blurb about it in the support but I wonder if there is more aspects to it.

Thank you for the quick reply, I didn't know it was a wide-spread issue. Still, if it's so common, maybe something more obvious could be put in the log for it?

Also it took me until I posted this thread to understand that the threads are in backwards order from most forums. This place is really hard to read for someone just popping in for a moment.

[vlado]

Also it took me until I posted this thread to understand that the threads are in backwards order from most forums. This place is really hard to read for someone just popping in for a moment.

You can change this in your user preferences - go to "Settings" in the top right corner of the page; from the left panel choose "General settings", find the "Thread Display Options" section, and for "Thread Display Mode" choose whichever option is most convenient for you. You can also customize many other aspects of how you view the forum.

Best regards,
Vlado

[aweidenhammer]

I really didn't mean to sound like a jerk. This is a common issue, and represents a significant portion of problems reported here. Perhaps simply upping the default Dynamic Memory Limit would be good. 500 is awfully low, and will often run people into problems. We have presets that up it to 6000 by default. We can assume most people have at least 4 gigs of ram to devote to rendering? Perhaps a better default would be 2000? This might result in fewer general complaints. In your case Steve, that would still be too low, but at least it would reduce the issue.

From postings I've heard from Vlado in the past, it looks like that feature will be getting some improvements in performance, so it may be moot to think too much about it right now.

Took me a few times here to get used to the forums too. I did switch ordering in my prefs, and am much happier And no, it was not in the post just before this one. I think it was in another section altogether. So sorry.

Andrew

[SteveMack]

No worries, it's just a bit frustrating as a TD with no VRay experience trying to help my lighters figure out what the hell is going on with a new render engine and we have a fairly unique pipeline, it can be hard to pin down where a 'bug' is coming from. Some hiccups are expected, tensions are running a bit high because of a deadline that we don't have time to render for, so any failure is going to sound like OMGCATASTROPHE

We will play around with the mem limit a bit and see what works. However, one thing I don't understand is how this affects the memory usage on the system. When a scene is rendering on a workstation with the Maya gui, it takes up 8-9 gigs of ram, when I render via command line batch, it just thrashes... Am I supposed to set my mem limit to 8-9 gigs, or..?

[vlado]

We are thinking of a different default value for 64-bit builds; since SP1, setting the limit to 0 means no limit at all and V-Ray will take as much RAM as it needs. Other than that, 2 or 3 GB below the physical memory in your system is often a good value.

Best regards,
Vlado

[gardeler]

@SteveMack
Just like you, I'm also putting vray through it's phases for the first time in production. I would be very interested in hearing about your conclusion on this matter as I'm sure I will find my self in the same spot in the near future. so maybe after you have compleated your project, would you mind posting your experiences? Like if upping the dynamic memory limit fixed your problems and so on.

Thanks

Marre

[vlado]

Something else to keep in mind: V-Ray will by default subdivide the mesh up to 8 times (max. 256 subdivisions along a triangle side), depending on its distance to the camera; often it's not necessary to go this high though.

Best regards,
Vlado

[treyharrell]

We are thinking of a different default value for 64-bit builds; since SP1, setting the limit to 0 means no limit at all and V-Ray will take as much RAM as it needs. Other than that, 2 or 3 GB below the physical memory in your system is often a good value.

Best regards,
Vlado

Vlado,

We've been trying to test setting the dyn limit to 0, however Maya's render globals / the vraySettings node won't take values outside of the 5-20000 range (build 12190).

Is there a specific build number where this took effect?

Thanks,

Trey