RAM, Cores, etc, how to best use

After Effects is the bottleneck here, not your Mac Studio. AE has a long history of being mostly single-threaded, so it can’t fully exploit your 20 cores or 128GB of RAM.

What you’re seeing (RAM half-empty, many cores idle) is normal.

Best bet: enable Multi-Frame Rendering in AE’s prefs (it should use more cores per frame), keep Media & Disk Cache on a super-fast SSD, and make sure GPU acceleration (Metal) is turned on.

If that still doesn’t cut render times, you’ll need to either render via Adobe Media Encoder in batches, break your comp into smaller sections, or look at third-party render engines/plugins that scale better.

The hardware’s not the limit..AE’s architecture is

You do not have control over what CPU/GPU resources After Effects uses while processing your video files. It will use the RAM, CPU and GPU cores that Adobe designed it to use for the given size and complexities of a given video file.

You may need a newer generation Apple Silicon chip to reduce your processing time, and if applicable, a current version of Adobe After Effects. There is only so much you can get out of an M1 CPU/GPU even in an M1 Ultra.

You can always ask Adobe if they have any recommendations that you have not tried in the After Effects settings to shrink your current processing time.

Caveat. I do not use Adobe After Effects.

Adobe – After Effects – Improve performance