on the question of namespace locality

In Plan 9, two different concepts are confused under the name "locality".
One, the concept of locality, and two, the concept of disconnectedness.
In Plan 9, you don't merely have local namespaces, you have completely
disconnected namespaces. In your everyday filesystem, a file is local to
the directory that contains it but it is not disconnected from files in
every other directory. So Plan 9 doesn't just have local namespaces, it
has *disconnected* namespaces; which according to reports is a Bad Idea.

The decision to go the disconnected route is actually an ugly kludge to
patch up a problem the designers refused to solve elegantly. The problem
is that users need local access to global resources. The simple solution
is to just hard link files you want access to, and that actually works
out pretty well. And if the resource is represented by a directory then
the problem is resolved by making directories hard linkable!

Now, if we've determined that disconnectedness is a Bad Idea then mounts
are unacceptable. Within a single filesystem, hard links make mounts
unnecessary and ugly. Between two separate filesystems, you need to be
able to create a hard link analogue; I call them portals. Portals are
not static entities like files or directories (even if synthesized at
run-time, files are comparatively static entities) but rather nodes
associated with an fid in a remote filesystem. If an fid walks through
a portal then the fid associated with the other end of the portal is
cloned and the #fid of the clone is associated with the fid stuck at
the entrance of the portal. From then on, any message sent to the first
fid is just bounced right back to the second fid. And portals, unlike
mounts, can be made bidirectional quite trivially.

No mount daemons! No added syntax! No disconnectedness!

--
Another poll revealed that "faith in God is the most important part of
Americans' lives." Forty percent "said they valued their relationship with
God above all else"; 29% chose "good health" and 21% a "happy marriage."
Satisfying work was chosen by 5%, respect of people in the community by 2%.
That this world might offer basic features of a human existence is hardly
to be contemplated. These are the kinds of results one might find in a
shattered peasant society. -- Noam Chomsky in "The Third World at Home"