I'm not the one having a library issue, I was simply offering that large libraries will take time to scan in.
I don't know if it's a library size thing or just something invalid causing a halt somewhere. I've got a rather large library myself and the only time I've seen something stuck is when the database gets corrupted or a file somewhere is corrupt and Emby isn't handling an error correctly. SQLite isn't the best DB handling crashes or spontaneous reboots/crashes. Certainly not saying this is the issue but you should perform a database check.
At a minimum I'd shut Emby down and try a "sqlite3 library.db "PRAGMA integrity_check"
You can google the Pragma integrity_check for directions.
Another thing you could try to narrow down the problem to a particular library is to restart Emby then do a library refresh one by one (start with smallest and work your way up). You can "cat" your log file to watch progress and see it working vs just looking at the status display as well.
I'd offer to TeamView or remote in and give you a hand but I'm not familiar enough with your OS and wouldn't feel comfortable enough to help in this regard.
BTW, have you thought about starting to replace your 4 TB drives with bigger ones yet? 12 TB drives are pretty reasonable these days and really help with density.
12tb drives are still $500+ and with my setup I need to swap 4 at a time. I've still got around 10tb of usable space plus 4 slots available for more drives. When I fill this case I'll have to start looking at other options. But this is all off topic and not helping the OP so I'll back out of this thread now.
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