Pixar's Render Farm

My understanding (I am not an authority) is that for a long time, it has taken Pixar roughly an equal amount of time to render one frame of film. Something on the order of 24 hours. I don’t know what the real units are though (core-hours? machine-hours? simple wall clock?)

I am not surprised that they “make the film fit the box”, because managing compute expenditures is such a big deal!

(Edit: When I say "simple wall clock", I'm talking about the elapsed time from start to finish for rendering one frame, disregarding how many other frames might be rendering at the same time. Throughput != 1/latency, and all that.)

Well it can't just be one frame total every 24 hours, because an hour-long film would take 200+ years to render ;)

I’m going to guess they have more than one computer rendering frames at the same time.

Yeah, I was just (semi-facetiously) pointing out the obvious that it can't be simple wall-clock time

Why can’t it be simple wall-clock time? Each frame takes 24 hours of real wall-clock time to render start to finish. But they render multiple frames at the same time. Doing so does not change the wall-clock time of each frame.

In my (hobbyist) experience, path-tracing and rendering in general are enormously parallelizable. So if you can render X frames in parallel such that they all finish in 24 hours, that's roughly equivalent to saying you can render one of those frames in 24h/X.

Of course I'm sure things like I/O and art-team-workflow hugely complicate the story at this scale, but I still doubt there's a meaningful concept of "wall-clock time for one frame" that doesn't change with the number of available cores.