If an admin mounts all file systems as -rshared (Default on RHEL and Fedora)
we see a scaling problem as the number of container increase.
Basically every new container needs to have it new mounts in /var/lib/docker
shared to all other containers, this ends up with us only able to scale to
around 100 containers, before the system slows down.
By simply bind mounting /var/lib/docker on its and then setting it private,
the scaling issue goes away.
Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
Upstream-commit: 792bb41e524615486ef8266b7bf4804b4fe178f1
Component: engine
6d04587343