Grafana/Telegraf show 0 bytes memory usage for docker containers

Today i searched for a problem with a docker container. Since there was a problem with the memory usage of the container, I wanted to check it in my Grafana. But unfortunately, the Telegraf plugin showed 0 bytes for each container since months. I founded the solution the the Telegraf GitHub issues. You need to enable memory control groups on Raspberry Pi. To do that, add the following to your /boot/cmdline.txt to enable this metic:

cgroup_enable=memory cgroup_memory=1

And after reboot, it works: