Kubernetes Dynamic Volume Provisioning gives a handy way to supply pods with dynamically-allocated storage volumes. For example, NFS Provisioner transparently spins up an NFS server and exposes that storage to client pods with Kubernetes volume interface, on-demand.
But how efficient is that? Does provisioner introduce another network protocol layer to communicate with client pod/container, in addition to NFS client-server communication? Or client pod/container talks directly to NFS server once the persistent volume claim was fulfilled?