Global file system quota not working as expected

I have a server connected to two clients. Server is backing up both client data to a storage server that has dedup feature enabled.
I created a CIFS filesystem of 1GB, configured maximum and minimum number of full/incremental backup, configured global file system quote to 5% i.e (50MB). I executed series of full/incremental backup filling ~120MB of filesystem.
I was thinking that cleanup will delete backup based on all configurations but when cleanup executed it deleted backups based on maximum and minimum number of full/incremental backup but global file system quota is not met. My filesystem still contains 117MB of data instead of <50MB.

Can anyone please explain what is going on here?

If all clients have their minimum number of each backup type then no further deletions are possible. If storage space is more important to you then you will have to set smaller mnimums (down to zero) for each client, or back up fewer clients. Frankly today when you have difficulty buying a new hard drive of less than 1TB size I can’t see allocating such a small backup partition, but your reasons are your own.

Maybe this was an experiment
fs quota can allow to fill the drive with backups as long as you as room for it, should be done in conjuntion with a high max backup.
But maybe you ll think that having 1000 backups for a single client is not that usefull , hence the max babckup setting.
And maybe it s not hat usefull if you have 99 clients to have 1 backup and 1 client have 990 backups , hence the min backup settings

There are two settings that control how much space is used by UrBackup.

Client: Soft client quota: is used to keep one client from using most of the storage space. It applies to each client in the group (default group if not otherwise set). I have mine set at 50% because I have a small number of clients. With a larger number of clients I would use 20% or smaller.

Server: Global soft filesystem quota: is used to prevent operating system problems when the storage device is nearly full. It determines the total space used by UrBackup. I set mine at 80% or 90% on a 2TB or larger drive, considering how many image backups or large file backups might occur in one day before the cleanup runs.

The “soft” part of the name means cleanup will still obey the minimum and archive settings and not delete backups you have said are needed.