Very high CPU load

I am facing a super high cpu usage which I am trying to investigate. The setup is quite simple:

  • docker
  • community edition
  • version 12, docker compose file almost untouched

After few seconds, htop show a cpu load of 40-50 (not percentage, absolute). Server gets unusable and I need to stop the container.

I tried the same exact deployment on a different server (a bit more powerful) and it works fine, cpu load is almost 0, as expected from an idle setup.
The server that suffers of high cpu load is a very cheap VPS (1 vcore, 2GB ram). I am more incline to look at software reasons more than hardware. Other services (like nextcloud) do not struggle at all.

Do you have any hint on this? Is there a way to investigate better? Maybe a debygging log?