HP open-sources the Tru64 filesystem

Actually, ZFS license is just a slightly more liberal Mozilla license.  It is GPL that
prohibits linking with anything that is not a subset of GPL.  That's why there are many
non-GPL-compatible licenses, but there are no non-CDDL-compliant, non-MPL-compliant or
non-BSD-compliant or whatever.  The full problem lies in GPL, not CDDL.

Of course, the "GPL" above is in fact "GPL as interpreted by RMS".

But I digress.

What I meant was, the usual way of doing stuff right now is a filesystem-on-top-of-lvm.  AdvFS
seems to have this two "layers" integrated together, just like ZFS.

And yes, AdvFS had it decade ago.