Ram Problem

[ben_hamburg]

Hi, I have a problem which I haven´t encountered before.
I have one shot that renders just fine up to a certain frame and after that I´m getting errors in the farm: Some nodes don´t render it anymore, and those that do, render the fluids black.
If I´m rendering locally I can see the ram usage spike very quickly during the "Building static raycast accelerator" stage, so I´m guessing it´s a Ram problem. I don´t understand why it´s only happening after a certain amount of frames (towards the end) though.
Skyline subdivisions are at 4, meshsmooth is also at 4.
The resolution is quite big because of the stereoscopy (4440 x 1080), maybe this causes the problem?
In that case it might help if I split the stereo images instead of rendering it in one pass.

[ben_hamburg]

By the way - do I still need to set default geometry to static or did that change after the official release? Because as I´m watching the render right now, the "Building static raycast accelerator" phase is at 18 minutes and not finshed yet...Changing default geometry didn´t seem to have any effect, so is there anything else I could do to reduce ramload?

[ben_hamburg]

I tried lowering skyline subdivisions and meshsmooth both to 2 and it seems to render now...

[ben_hamburg]

Nope- still the same result: some nodes render, some don´t...

[Ivaylo Katev]

yes, yesterday another user reported very high ram usage during ocean rendering, i bet it's related to the changes that we introduced last week, apparently in some cases very high triangle count is generated.
this is a bug for sure, because by idea the changes decrease the triangle count, and in the test here it was exactly as planned.

[ben_hamburg]

Oh, alright then, thats unfortunate, but good to hear, because I was already thinking about doing a resim and hoping the issue would be gone then. So I´ll just wait on an update from you guys then, I still got some time to render. If it turns out to be a bigger problem, i´ll just resort to using Cap mode with vraydisplacement ocean and blend it in post.

[ivaylo.ivanov]

You can also use an older build from 17.

[ben_hamburg]

Ok, in case I can´t fix it otherwise I will revert to that build.

[ben_hamburg]

Hi there, is there any news on the ram issue?
Because I ran into the same problem with another scene and that one is less easy to fix with Vraydisplacement and blending...
I already checked nightlies and I didn´t find a build from the 17th, there is one from 18th and one from 15th, which one should I revert to?

[ivaylo.ivanov]

The older one, from 15th. Can you test with it and repord back if the scene renders fine with it?

[Ivaylo Katev]

it would be very helpful to send us the scene and the cache file that produces the problem, i hope we will be able to fix it in short time.
no need to send the full production scene, just the simulator and the camera, can remove the geometry

[ben_hamburg]

I´ll strip the scene and send it to support. I might have to send the cache file via wetransfer because it´s around 80 MB.

[Ivaylo Katev]

ok, thanks!

[Ivaylo Katev]

ok, the bug is fixed, try with the tomorrows build

[ben_hamburg]

Ah, that´s great, right in time for the weekend render marathon!