docker-containerd experiences growing RSS/memory consumption when `docker exec` calls are run

Issue

• When using Docker as provided by Red Hat, we observe memory consumption in the form of growth in Resident-Set-Size (RSS) for the docker-containerd process.
• Specifically, containers have exec called on them frequently, which is frequent in scenarios when using the following in your environment:
  • Docker healthchecks
  • OpenShift livenessProbe or readinessProbe where an arbitrary command is passed instead of http or tcp, such as curl or ping.
  • Any facility that frequently calls docker exec from either the command line or via the Docker API.