Used Space info above. Here's a breakdown of "Other" listings - both Owner and Knox with the amount of space used for each folder recorded:
Owner Other (1.28 GB):
Voice Recorder - 0.00 B
Simple Notepad - 2.11 KB
Samsung - 3.21 MB
Ringtones - 0.00 B
Podcasts - 0.00 B
Pictures - 0.00 B
Notifications - 0.00 B
Music - 0.00 B
Movies - 0.00 B
Download - 3.66 MB
DCIM - 53.14MB
CanonIJ - 0.00 B
CalendLunImages_cache - 596 KB
Android - 204 MB
Alarms 0.00 B
KNOX other (1.71 GB):
Voice Recorder - 0.00 B
Simplenotepad - 2.11 KB
Samsung - 3.21 MB
Ringtones - 0.00 B
Podcasts - 0.00 B
Pictures - 0.00 B
Notifications - 0.00 B
Music - 0.00 B
Movies - 0.00 B
Download - 3.66 MB
DCIM - 53.14 MB
CanonIJ - 0.00 B
CalendLunimages_cache - 596 KB
Android - 2.04 MB
Alarms - 0.00 B
Let me know if there's anything else you need
BTW I've hit "3 GB free" for the first time tonight. Clearing the cache has taken the phone back to "3.3 GB free" but it's the first time since the factory reset that it's gone that low...