Tech support got back to me with the solution it seems.

In Alembic properties there is a 'History Depth' option. This seems to be the cause of the memory leak. Think this is always useful if you want a trail effect or something that would require data from the previous 10 frames (I think by default). I turned History Depth down to 1 and the frames are now all rendering for the same amount of time.

Not sure whats happening here, but scenes in which I have these alembic models are taking progressively longer to render with every frame in the sequence. Ive optimized the scene to render out at about 2mins a frame. This being anywhere in the sequence if I randomly render any frame by itself. about 2 mins.

But when I put it in the queue, redshift slowly creeps the time up as the sequence goes on, only about 30 frames in each frame had jumped to almost 10mins. Unrendarable.

The alembic is a tree model. The leaves have a jiggle deformer affected by a turbulent field to give them some slight movement. That is the reason I have exported it out as alembic.

Is there something I am missing here?

For those that have got the same error, I still dont know what it was.

My workaround was to redo the take, delete the old one. It was something in there that maybe I changed? No idea.

Shock, horror!

Ive been adjusting a scene all day with the RS window open, not doing anything crazy, repositioning some lights when suddenly the RS renderview goes black. CRITICAL ERROR!

Unresponsive, I restart C4D. Try to open the project and hit RS renderview again. Update Redshift to newest version. Boom, same error. Has my GPU just fried?

Heres the kicker. Open a different project. RS is working fine. Another. Fine.

Open the same project, boom! error! remove a large tree.....working?...

So im guessing its a memory issue? point is, I didnt change anything with the tree. And its been rendering it all day fine. Now, no. Any suggestions? Here is the log file:

20:03:40 7963MB ERROR:
Writing Redshift crash dump to C:\Users\joshe\AppData\Local\Temp\Redshift\20251010-200340-27928-22476.dmp
20:03:40 7948MB DEBUG:
Crash dump succeeded.
20:03:40 7936MB DEBUG:
Critical Error Detected
Redshift encountered an unrecoverable error and has been disabled.
Cinema 4D may be in an unstable state.
We recommend you save your work and restart Cinema 4D.
20:03:40 7935MB ERROR:
Critical Error Detected
Redshift encountered an unrecoverable error and has been disabled.
Cinema 4D may be in an unstable state.
We recommend you save your work and restart Cinema 4D.

I opened your file and it renders in 18 seconds. I have not cached my scene rigid bodies. I fail to see how that would affect the render, as it is as I said before, immediately rendering to the viewport.

Appreciate the help on this Sassi boy

Here is the link to the project file: https://www.dropbox.com/scl/fi/i1oqb6trlx0zfbeyl1ai1/FirstLights_Geraldton_V04.c4d?rlkey=nx6vr4bxck1lm3ufzhp9i4twy&st=tnmla0wi&dl=0

Its a very simple setup, there are a bunch of cloners, 8 to be exact. All with varying amount of clones of spheres with 16 subdivisions. The total number of clones/spheres in the scene from these groups is 240. They have one shader applied to all. This is using the color data connected to the emission.

Effectors are mostly inheritance to move the spheres from one cloner object to another. There are others that control colour, very simply with a shader field and box field. There are rigid bodies on each sphere, for collision spacing. Could it be this? Some sort of calculating in the background? despite it rendering immediately in viewport. This is the biggest confusion.

Have just made scene with 600 spheres, same material and colour effector. It renders immediately. More sass please or I'll throw C4D into the sea.

Creating a drone show. Basically a swarm of spheres with the effectors controlling their position and colour via the luminance channel. Simple.

Render is immediate when done to viewport. Rendering to picture viewer takes almost a minute per frame, if not more. Ive complex scenes with GI and volumetric lighting that render quicker than that. What is going on?

To reiterate. 0 lights, only the emission channel needed. I have tried this in both redshift and physical/standard renderer. All the same.