Different files space in container mount point

[digidax]

Hello,
I have add a mount point, based on a hardware RAID-0 (Stripe) to a CT:


Inside of the LXC container, I get:

# df -h
Dateisystem                  Größe Benutzt Verf. Verw% Eingehängt auf
rpool/data/subvol-211-disk-0  200G    133G   68G   67% /
/dev/loop0                    6,8T    1,3T  5,3T   19% /backup_spool
none                          492K    4,0K  488K    1% /dev
tmpfs                         2,9G     16K  2,9G    1% /dev/shm
tmpfs                         2,9G     89M  2,9G    3% /run
tmpfs                         2,9G       0  2,9G    0% /sys/fs/cgroup
tmpfs                         593M       0  593M    0% /run/user/0

The mont point /backup_spool of the /dev/loop0 file systemen hast 1,3T of 6,8T in usage.

But if I check on the node:

root@pve4:~# df -h | grep backup_spool
/dev/sda1                     7.3T  6.4T  539G  93% /mnt/pve/backup_spool

There are used 6,4 T, produced by the disk Image:

root@pve4:/mnt/pve/backup_spool/images/211# du -sch *
6.4T    vm-211-disk-0.raw
6.4T    total

Why is it so and what can I do, to deflate the disk image on the node?

Kernelversion: Linux 5.4.128-1-pve #1 SMP PVE 5.4.128-1 (Wed, 21 Jul 2021 18:32:02 +0200)

PVE Manager Version: 6.4-13

Thanks and all the best, Frank

 

[digidax]

Brining this question up again, I'm planning to upgrate to 7.0 but want to have clearness, that this problem will not destroy anything.
Are additional information needed?
Thanks.