XAVC S 4K 100P 1/200 4:2:2 10 bit chops in Premiere Pro

[Joel26238093ifjt]

I really need help and hope to get it.
XAVC S 4K 100P 1/200 4:2:2 10 bit chops in Premiere Pro. What is it due to?

Video camera:
Sony FX3

Apple computer:
iMac Retina 5K, 27 inches
Processor 3.8 GHz 8-core Intel Core i7
Memory 64 GB 2667 MHz DDR4
Graphics SMD Radeon Pro 5500 XT 8 GB.

Even if I change the "resolution" setting in Premiere Pro to 1/8 the movie still chops.

What can I do so that the film can roll perfectly without stuttering?

[mjshade]

I'd imagine editing with proxies would resolve your issue. If your computer is struggling with the codec, then changing the playback resolution isn't going to improve your performance. Maybe try it with a few files and see if your performance improves. 
https://helpx.adobe.com/premiere-pro/using/ingest-proxy-workflow.html

[R Neil Haugen]

All the XAVC codecs use long-GOP compression, so they're hard as Hades on an NLE to begin with.

And it's what, a 4k 10 bit file at what's the framerate ... 100fps?

Yea, that's a load right there. Proxy the stuff. Note, your proxies need to be in an intraframe codec for best playback. Like ProRes, Cineform, or a DNx variant. Which means they'll be much larger on disc than your original clips, but vastly easier on your system for playback.

Neil