I don't see docker id inside /sys/fs/cgroup/

Expected behavior

'm expecting to see a folder with containerID in the location /sys/fs/cgroup/ as long as the container is running

Actual behavior

Intermittently, I don’t see the folder with name container ID inside /sys/fs/cgroup/

Additional Information

We are using Kubernetes to deploy the pods. We have datadog agent deployed as container on the node (amazon vm). The datadog container has the /sys/fs/cgroup/ mounted and tries to fetch the /sys/fs/cgroup/cpu/docker/containerID/cpu.stat file. The datadog agent is returning error as it doesn’t see the containerID insider /sys/fs/cgroup/ .

The issue is intermittent but happens frequently. Some time I do see container ID folder inside of the /sys/fs/cgroup/ location and for some time not though the container is running.

How to debug this issue?