No free space after deleting files?

Question

linux

Actually a subject.
There is a home server.
On it there is a faylopomoyka
/dev/md0 688G 613G 41G 94% /home/user
in raid 0
Works Transmission-daemon.
Yesterday, with the help of transmission-remote-gtk, I removed several torrents from the distribution with deleting files.
the files were gone, the torrents too, but the disk space was not freed up, I deleted more, but it was never freed up.
I thought the Transmission bug, rebooted the demon, did not help.
Looked in lsof there it is empty.
Reboot the server didn't help either.
It should be free about 75 GB, and only 41 are free, and then it was possible to delete it with the release of space only after the reboot.
Unfortunately, the transmission logs were not written at that time.
I thought, maybe 1 of the disks fell off, the disks poked, everything is in order.
in general, some kind of devilry has already broken his whole head, why can this be ??

Answer 1

5% of the partition space is reserved for root.
answer in the comments in the post by Sergey Ovechkin Sergey Ovechkin

Answer 2

Well, in Linux, each file is presented in a single form on the disk and it can have several links in different folders or programs. it seems that some program opened or copied it, and as a result, after deletion, the file still had links and therefore it could not be deleted from the file system.
perhaps glitches in the file system itself, it is necessary to check (of the file system, not the surface).

Answer 3

Trash check ~/.local/share/trash