Rt ram usage vray 3.01.10

[super gnu]

just doing a quick but heavy test of RT GPU and forestpack.

wanted to see how much i could cram into my 4gb gpu.

its a 25 sq km bumpy plane with a forest object referencing 6 instanced proxy trees, with a fairly dense scatter.


in normal vray, it uses 6gb in total when rendering.. this includes max and viewports etc. using progressive sampler ( all at defaults in vray actually)

so in theory shouldnt be far off fitting in the gpu ram.


However, when i switch over to rt gpu, it gets to the "compiling geometry" stage, in the vray rt floater, and my ram usage just goes up and up.. currently at 26gb and still slowly climbing. (after about 5-10 mins of waiting)

vray rt hasnt even started doing anything yet, and my gpu is only using the 1gb it was before i started.

is this expected..? bit odd that rt gpu should need so much system ram to deal with a file that renders without stressing my system at all normally.


-update, my ram is now maxed out at 32 gb and still nothing has happened. i guess ill be cancelling.


edit:
i cut the forestpack back to a smattering of trees, and now it "only" hits 10.5 gb of ram usage before sorting itself out and starting the render.

update: rt cpu behaves properly, uses only 6gb when rendering.

[vlado]

This is strange; do you think you can get me the scene to vlado@chaosgroup.com ?

Best regards,
Vlado

[super gnu]

sure can.. ill send it later this eve..

[super gnu]

ive sent you the file via wetransfer

[super gnu]

in case it matters, im using max 2014 x64, and forest pro 4.3.4

[matanov]

I've reproduced the problem, thanks.

[super gnu]

just wanted to note that this problem still persists with vray 3.20.02

[Svetlozar Draganov]

That's correct, the issue hasn't been solved yet.
We'll let you know when it is.

[super gnu]

could somebody clarify what the problem is? i.e. forestpack is broken with RT gpu? or just specific features/usage scenarios i should avoid..

[vlado]

I don't know what the problem is yet. One of the developers is looking into it.

Best regards,
Vlado

[auke]

I have been having the same problem in some scenes (without using forest pack). It is a fairly large scene and should be rendered on 4000*2828. Translation seems to stop after building global light manager, follow diagnostic massages only arrive after a long time (even though they do have a timestamp indicating they happened only seconds after previous opperations). Vray RT rendering (GPU) then starts but finishes after just ~4 seconds, no warnings or problems noted in the diag screen. The Max/Vray render progress bar panel keeps showing it is rendering without anything actually happening. I noticed the problem started when I reached 90+% of my ram (16GB). Rendering on quarter resolution seems to work properly. Very curious if this is a software issue or I should just expand my RAM. ps, Scene is rendered on a Titan X and GPUz states it's max VRAM use was 5gb while then Vray RT diag screen reports a usage of 8GB.

[matanov]

You can put more ram or just for a quick test try disabling windows paging and render, in that case 3ds max should crash (if the problem is insufficient ram).

[auke]

Would there be a way to know how much ram would actually be needed for this translation phase? As I probably could get an upgrade for my workstation, it would be less than fun if the problem persists with double the ram. Or is this ram consumption impossible to predict?

[vlado]

I think we fixed some issues related to this recently. Would it be possible to send a scene for testing?

Best regards,
Vlado

[auke]

I'm afraid the scenes in which I experienced this problem included alot of assets which I can't share. The scenes did include large numbers of instanced objects, proxies (trees) and was supposed to be rendered at high resolution (4500*3000). I don't have time to create a completely new scene to replicate the problem at the moment. If needed I'll try to throw something together in more quite hours.

ps. Attached a picture to the wrong post, nevermind the image, maybe a mod can remove it?