logs filling root disk

In this folder all task logs are stored.
well, yes but in a sub folder, there are other logs in there too, so to be sure: is it really in /var/log/proxmox-backup/tasks or e.g., in /var/log/proxmox-backup/api.

The version in use would be also interesting: proxmox-backup-manager versions --verbose

For tasks IIRC there was a recent fix in PBS `2.0.13-1` which also cleaned up the tasks once their reference got rotated out of the index.
 
The PBS is still running a older version, so I think the update should fix this problem.
Code:
proxmox-backup             2.0-1        running kernel: 5.11.22-5-pve
proxmox-backup-server      2.0.12-1     running version: 2.0.12     
pve-kernel-helper          7.1-2                                     
pve-kernel-5.11            7.0-8                                     
pve-kernel-5.4             6.4-4                                     
pve-kernel-5.11.22-5-pve   5.11.22-10                               
pve-kernel-5.11.22-3-pve   5.11.22-7                                 
pve-kernel-5.11.22-1-pve   5.11.22-2                                 
pve-kernel-5.4.124-1-pve   5.4.124-1                                 
pve-kernel-5.4.119-1-pve   5.4.119-1                                 
pve-kernel-5.4.106-1-pve   5.4.106-1                                 
pve-kernel-5.4.65-1-pve    5.4.65-1                                 
ifupdown2                  3.1.0-1+pmx3                             
libjs-extjs                7.0.0-1                                   
proxmox-backup-docs        2.0.12-1                                 
proxmox-backup-client      2.0.11-1                                 
proxmox-mini-journalreader 1.2-1                                     
proxmox-widget-toolkit     3.3-6                                     
pve-xtermjs                4.12.0-1                                 
smartmontools              7.2-pve2                                 
zfsutils-linux             2.0.5-pve1

The Exact folder with the 100GB logs was /var/log/proxmox-backup/tasks