PBS completely full disk

Hello.

I have a remote PBS with 2 disks as a ZFS-mirror. It all worked great but the disks got completely full so it is not operable anymore. I can access it through GUI and SSH, but I can only run few commands. I have deleted almost every log and most of its backups and then waited for more than 24 hours, but no difference.

What else could I do?

I don't mind loosing every backup it has.

Thank you