Help Understanding Content Tab's Reported VM/LXC Backup Size?

[SInisterPisces]

Hello,

My Proxmox node uses thin-provisioned ZFS storage. So, for instance, I might tell a VM it has a 64 GiB VirtIO SCSI disk, but that disk might realistically be using much less than that.

The way Proxmox Backup Server reports space usage for backups is confusing me.
My actual datastore summary for a nearly empty test PBS instance looks as I'd expect for actual storage being used:


On the other hand, the Content tab appears to report how much actual space an LXC backup uses, but reports the maximum possible size for each VM.
That LXC has an 8 GB virtual HDD attached, but is reporting a size in the 3.7 GiB range.
The VM, on the other hand, is reporting its sizes based on the maximum size of the attached VirtIO SCSI devices. Actual space used (according to checking disk sizes inside the VM itself) are much smaller.



Is this what I should expect to see, or have I done something wrong? I certainly haven't used 105 GB of my available 150 GB of storage on that server.

 

[fabian]

this is expected, because PBS doesn't have a breakdown of deduplicated storage use down to the group/snapshot level

you can look at the upload stats in the snapshot manifest (index.json.blob), but that only tells you how much was needed to be transferred at the time the snapshot was made..

 

[fabian]

https://bugzilla.proxmox.com/show_bug.cgi?id=4506

 

[SInisterPisces]

Thanks for the info, and the link to the bug report. I just wanted to make sure it's working as intended and that I hadn't broken something. Again.

Mostly, I just wanted to make sure the Usage percentage in the Datastore --> Summary tab (first screenshot) is an accurate picture of my overall real disk usage. It's what I've always used before, but once I looked at the guest space usages, I started second guessing myself.