[pbs-devel] Timeouts on Proxmox Backup Server

[Mark Schouten]

Hi,

We are suffering from some slowness in Proxmox Backup Server, which results in timeouts in Proxmox VE and monitoring-notifications thereof. We’re looking into why this is happening, but I cannot really find anything wrong with the setup.

As you may know, we have a few PBS-machines running with more than a few users on it. The machine that suffers the most of this issue is pbs001, which is handling about 34 authentication requests per second. We have over 250 users on that machine. What I notice is that even though there are no tasks running, we see quite a lot of CPU usage:


    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
3035778 root      20   0  857840  27900  14124 S 163.7   0.0  59:22.43 /usr/lib/x86_64-linux-gnu/proxmox-backup/proxmox-backup-api
   7658 backup    20   0 6603600 528644  14004 S  74.5   0.8  40706:05 /usr/lib/x86_64-linux-gnu/proxmox-backup/proxmox-backup-proxy

When stracing PID 3035778, most output I see is the reading of the file '/etc/proxmox-backup/tfa.json’, one byte at a time.

Could it be that this part of authentication could use some optimisation?

Happy to help, if we need to provide information about this machine or the setup. Please let me know.

— 
Mark Schouten, CTO
Tuxis B.V.
mark at tuxis.nl