https://lists.proxmox.com/pipermail/pve-devel/2021-May/048220.html
[pve-devel] [PATCH v2 container] fix #3421: allow custom storage plugins to support rootfs
pvedevelpatchcontainerfix
https://www.chromium.org/chromium-os/developer-library/guides/image-size/visualizing-the-rootfs/
Visualizing the Rootfs
visualizing the rootfs