render issues large scene Tweet

[djiin]

If you try and render the parts as a whole as your first render when you open Maya (open maya, render your whole object literally before you try rendering anything else) does it render? Then if you stop the the render, you can't start it again until you restart maya?

That's the situation I'm in...I literally have to restart Maya every time I need to restart a render after having stopped it. I'm running 1080's and the vram usage is somewhere in the 6-7gb range, so i've got plenty of headroom. I have been slammed with deadlines at a new job so I haven't been able to export to standalone to see if results are the same there, so I haven't badgered devs on this problem till I have time to test it. I

I'm wondering if the initial render isn't flushed out of vram when it's stopped (only flushing when Maya is closed down), so it's effectively trying to hold multiple instances of my scene in vram every time I render, well surpassing the 8gb's on my cards after the first render. If i'm rendering smaller portions, like you, I can stop and restart renders fine but I'm wondering if that's only because I haven't done that enough to reach the vram capacity of my card.

sometimes yes and sometimes not, i also have to reboot maya sometimes when it is not rendering anymore and then it renders again, i think you're right about the flushing.


on the note of Obensubdiv- is it lower memory usage to actually smooth the polys in maya vs using octane open subdues?

yes i think it is, without having that out of core setup, if my low poly were divided in maya the scene wasn't rendering, with no subdivision and geometry set to reshapable with octane level 3 it was rendering.

[calus]

I'm wondering if the initial render isn't flushed out of vram when it's stopped (only flushing when Maya is closed down), so it's effectively trying to hold multiple instances of my scene in vram every time I render, well surpassing the 8gb's on my cards after the first render. If i'm rendering smaller portions, like you, I can stop and restart renders fine but I'm wondering if that's only because I haven't done that enough to reach the vram capacity of my card. I could be way off though (as I mentioned, I haven't had time to test different situations yet) but it sure is acting like vram runs out after the first render.

Did you have this problem with every version ?
I didn't notice that with recent release, and it would be a shame, as one of the main advantage for me of Octane over other GPU renderer for Maya is that it's the only GPU renderer out there to correctly flush VRAM after a render.

on the note of Obensubdiv- is it lower memory usage to actually smooth the polys in maya vs using octane open subdivs?

In my tests Maya smooth and Octane opensubdiv use the exact same amount of VRAM, but when you smooth geometry in Maya it will use also obviously more VRAM of the display GPU, so if you also use this GPU to render it can be a problem.

[itsallgoode9]

Looking at it further, in my situation, when I restart a render, the GPU is definitely rendering/trying to render (graph shows full usage in GPU-Z) but the image in IPR just isn't updating...nor does Maya show any indication of rendering (sampling level info etc. doesn't show below the image). So it seems something in the background IS happening.

EDIT: I just noticed raising my out of core ram higher than the default (arbitrarily put it at 12gb) mostly fixes this problem for me (i still have to restart sometimes to restart a render--just not EVERY time). I assume that HAS to mean it's a VRAM flushing issue of some sort that's causing some sort of interference with the render view not updating?

Are you seeing that as well, djiin? I don't want to hijack your thread if we're actually having different issues.


@calus I just recently started using v3 a month or so ago, so I've only tried a couple releases and I don't recall which versions but the problem has been there with every one I've tried. I am not on the VERY latest version right now...I'm on two versions ago, which is whatever version was before the insta-crash one that they just fixed.

[djiin]

@itsallgoode9
i i have set the out of core to 16gb and still has to reboot maya sometimes but ok, as long it renders that's ok for me. as you notice it looks like it renders background and IPR not updates, same for me.
don't worry, you're not hijacking nothing, i'm new to octane and every time i try a lot of things before posting here and i always do it thinking i'm so stupid because many users are doing great with octane so i feel less alone when i point out on issues other users face too

[djiin]

and btw, MANY THANKS to all the prompt replies and solutions here you guys post, when you work it is so pleasant ,you can then go on further with your work.

[calus]

and btw, MANY THANKS to all the prompt replies and solutions here you guys post, when you work it is so pleasant ,you can then go on further with your work.

well, more hints for later then :
- not sure which version you are using but the last version 3.05.2 - 9.19 have a lot of bug fixed.
- try to not use more than 2 opensubdiv subdivisions level, it's a CPU process and it can slow-down a lot export time if too much subdivisions.
- if your objects are not deformed but just animated you should use the "movable proxy" type instead of "reshapable", opensubdiv works with that and when rendering animation with "animation mode : movable proxy", export time for each frame will be much quicker as only transforms are updated every frame.
- Render animation using the command line batch render, not the batchrender from inside Maya as it use less ram and vram.(Maya viewport use lot of vram).
- or don't use the GPU used for display also for rendering, don't forget that the Max VRAM you can use with Octane is decided by the rendering GPU having the less VRAM available.