[SOLVED] Datastore usage wrong

[Nimo]

Hello,

I wonder how the datastore usage is calculated. As far as I could find information it should be the fs size.

root@PBS:~# df -hT /mnt/datastore/TrueNAS-HDD
Filesystem     Type  Size  Used Avail Use% Mounted on
/dev/sdb       xfs    12T  476G   12T   4% /mnt/datastore/TrueNAS-HDD

root@PBS:~# du -sh /mnt/datastore/TrueNAS-HDD
241G    /mnt/datastore/TrueNAS-HDD

So I'd guess PBS would report a usage of 476G. But it tells me

while GC reports

2026-06-14T08:18:20+02:00: processed 99% (132673 chunks)
2026-06-14T08:18:20+02:00: Chunk cache: hits 942600, misses 128199 (hit ratio 88.03%)
2026-06-14T08:18:20+02:00: Removed garbage: 20.162 GiB
2026-06-14T08:18:20+02:00: Removed chunks: 5833
2026-06-14T08:18:20+02:00: Original data usage: 4.083 TiB
2026-06-14T08:18:20+02:00: On-Disk usage: 240.218 GiB (5.74%)
2026-06-14T08:18:20+02:00: On-Disk chunks: 128199
2026-06-14T08:18:20+02:00: Deduplication factor: 17.41
2026-06-14T08:18:20+02:00: Average chunk size: 1.919 MiB
2026-06-14T08:18:20+02:00: queued notification (id=f5c4906b-baed-4caa-9c8d-fe1568d83eb8)
2026-06-14T08:18:20+02:00: TASK OK

/dev/sdb is a iscsi netdrive xfs formated. It is a zvol on truenas.

So why is PBS telling me a usage of 510.99GB??

 

[Impact]

It's just different units. One is in Gigabyte (GB) and one is in Gibibyte (G/GiB).

 

[Nimo]

hmmm, a little embarassing I did not think of that, but yes, true...