Much traffic from rancher-agent

We’re currently performing a load and performance test on our application deployed on Rancher. I noticed that there is a lot of traffic from the Rancher agents (about 2 MBps). At the same time the agents show up as Disconnected / Reconnecting, which is probably a problem of our provider.

However: What are the Rancher agents actually sending? I would have expected that only meta data like “start container XY” or “container XY died” would be transmitted. What else is the responsibility of this container?