I'm getting tired of seeing output like this on my security scans:
usr/local: 
        type (dir, link)

Should I be using nullfs mounts to avoid this?
I'm not aware of the vagaries of the stackable fs so I don't know which
is really better, in terms of memory & performance, etc.

I'm also looking for papers on file systems in general... anything
web-accessible that would bring me up to speed with respect to terminology,
etc.