I started the scan for my movie collection (roughly 140 movies) on my Raspberry Pi 3B. It has become unresponsive and I can't ssh in now. It seems to be due to all the ffmpeg instances. I have two questions:
Should I wait for an hour or should I just reboot the server? Also, is there a way to disable the setting for chapter images from the web UI? I can't find it in the setting.
It is running ffmpeg which is likely converting your videos (or possibly extracting thumbnails).
I'd look in the settings and see if there's something related to that you can turn off.
Besides the obvious transcoding, trickplay or movie miniature generation will do that to you, yeah.