[SOLVED] Garbage collection doesn't delete anything

[tstrand]

I noticed the disk usage was steady going up on one of our PBS servers.





So I started to look at the prune & GC logs.
Prune seems to be working. for example "2024-07-16T07:43:46+02:00: Pruning group proxmox:"vm/265""

But Garbage Collection does not seem to delete anything. Each day It just runs and says

Removed garbage:      0 B
Removed chunks:       0
Removed bad chunks:   0

Leftover bad chunks:  0
Pending removals:     0 B (in 0 chunks)

Original Data usage:  242.646 TiB
On-Disk usage:        34.228 TiB (14.11%)
On-Disk chunks:       19421770

Deduplication Factor: 7.09

Garbage collection successful.

I have temporary stopped the backups to prevent the disk from getting full.
Nothing has changed on the server so I'm really confused why this has started to happen.

root@ubp-pbs02:~# zpool status
pool: pbs-backup
state: ONLINE
scan: scrub repaired 0B in 1 days 08:10:24 with 0 errors on Mon Jul 15 08:34:26 2024

I have tried going to Datastore - storage - Content And manually clicking on the red trash bin on some older snapshots just so I can see that it really does clean out some older chunks. And then waited 24 hours and manually ran Garbage collection. But it still comes back with Removed chunks: 0 and Pending removals: 0

running Backup Server 3.1-4

Any useful tips or clues would be greatly appreciated

 

[fabian]

maybe the snapshots you pruned don't actually cause any chunks to be no longer referenced anywhere? e.g., if the delta to the snapshot before was empty, or if there is another copy of the same snapshot in a different group or namespace this can happen..

 

[tstrand]

Thanks for replying fabian.
A reboot of the server seems to have resolved the issue.