I have a scene with im trying to get rendered out, has moving geo, flip fluids and some other elements, it seems to render fine enough, the main geo take about 10 minutes per frame to render, then at frame 172 it grinds to a hault and starts taking 8 + hours to render.

Nothing special is happening or changing on this frame, (The main Geo has no changing point counts or anything) and the render slows here on each mantra node for each specific render element (Geo/Fluids) and Micropoly/raytracing doesn't seem to change anything..

Im out of ideas but im running out of time on this project, any advice where i could look into the problem for this? its a heavy scene with many caches so i cant upload the scene as is.. could throw up the shell with just the lights and mantra nodes but not sure that will help much?

lighting is a few spot lights/area lights a sun/skylight and an environment light… but again it renders fine up until this frame so i don't think the issue is in the lighting or anything

Im running with the preformance monitor now il see what insight that offers

Any thoughts would be appreciated
-Nick

Hi

have you thought about rendering the geo separately and then comping it in?

could you link the hip file?

Hi,
If you are rendering with motion blur and any objects like particles pass through or very close to the camera focal plane it will cause render times to suddenly blow out !

Rob

I do have motion blur but nothing is getting very close to the camera or changing to much over all from the frames before it, frame 171 is fine but 172 slows way way down..

I Finally managed to strip down the scene to a size i could post so here it is if some one could take a look that would be great

… if i take out both the environment light and skylight it goes away, or if i cache out just the frame 171 and 172 and only read those in the scene goes away, so i tried splitting it up into 2 geo caches but that doesnt seem to do the trick, not sure why that would be the issue anyway as it seems to happen on this specific frame.

i could re light the scene if i really need to but id love to know why this is happening, but its frustrating that i cant reproduce the problem in a file im able to upload.

Thanks for the thoughts