"This post's twist is that we'll be specifically
approaching hiding data in ZFS mountpoints. For the purposes of our
demonstration and experimentation, we'll assume that the version of
ZFS we're using is the one that roughly corresponds with the date
of this post. If any feature mentioned didn't work a year ago, or
you're reading this in the future and find yourself disgusted with
the lack of an "obvious" and simple solution that didn't exist yet,
we beg your pardon. This blog is written in the present (over and
over and over again), edited in the very near relative-future and
published before the aforementioned activities become distant
recollections from the past ;)
"Again, you can refer to our previous post on finding space hogs
on multiple-overlay mountpoints if you want to look into that
aspect a little bit deeper. Also, we'll be using the /usr/local
overlay mount, mounted on top of /usr, for our models."