When i log into a user profile an automatic library scanoccurs, but this causes 4k content to stutter until its finished - is there any way to stop the library scan once content starts to play?
The only solution I can think of is to turn off
Update library on startup and just update the library manually when you aren’t watching content.
Once a scan starts it will run until you manually cancel it. Unless you constantly are adding new content I’d suggest that you turn off the scan on login.
You could use texturecache.py and schedule a scan daily at 2AM (any time you choose) via cron.
This will probably be resolved in Kodi v18 by the threading re-work; so that the video playback thread has a higher priority.