I wish there was a way to evolve plan9 into a modern
Unix.
Making an existing modern Unix diet into a lean OS is close to
impossible.
But if you try to turn Plan9 into a lean UNIX, you lose everything that Plan9 advocates.
In particular, I don't see how you can possibly integrate namespaces into UNIX in any
meaningful way. Without those, it's no longer Plan9, and therefore a pointless
endeavour.
A unix kernel boils down to a few subsystems: device
drivers +
device switch, scheduling, VM, networking and network switch,
filesystems + filesystem switch, interrupt handling, process
management. Some graphics support. A bunch of this can be
pushed out of the kernel without much loss of efficiency. And
may be the original design decisions of Unix need to be
revisited for 21st century hardware.
The release of the 10th Edition UNIX source is much more enlightening. Here you can see a
fully functional UNIX with what, 29?, system calls? And you can see the genesis of many
of the Plan9 concepts (/proc, dial(), mk, mux, etc).
--lyndon