A Summary of Project so far [Re: Kernel LISP - how low down can it go?]

Dwight Hughes dhughes@intellinet.com
Thu, 22 May 1997 02:59:12 -0500

| From: Henry G. Baker <hbaker@netcom.com>

 [ some great comments on threads, synchronization, and oodbs snipped ]

| The amazing thing about Lisp & OS is that while we think we have a
| pretty good handle on _memory_ management (i.e., GC), we don't seem to
| have a very good handle on _time_ management.  What is the equivalent of
| 'bounds checking' for time slots?  What process allocates time and
| reallocates it at the end of the time slot?
| If you plot critical sections wrt to processes and time, you find a
| kind of a vortex or a knot in the topology.  Perhaps there is an
| insight there that can be used to simplify our thinking about these
| problems.
| I realize that this is pretty researchy, but every successful _new_
| system has some small degree of innovation.  I hope that much of LispOS
| innovation is of the form "cut away the fat, cut away the bandaids and
| the chicken wire", rather than creating new levels of bandaids.

I can certainly agree with this, which is one reason I remain skittish
about basing everything on ANSI Common Lisp. Your comments reminded me
that when a number of sharp people are running in circles, like this
list has done on the issue of OODBs/POSs/OOFSs and their relation to
a multi-threaded OS, then there are probably some crucial issues that
are not understood properly - usually buried under some unexamined
assumptions (things "everyone knows" that one never questions). Geez,
now I'm going to have to use my brain for something other than keeping
my ears apart.

| Those of you who aren't familiar with Rodney Brooks's 'subsumption'
| (layered) architectures for mobile robots should have a look.
| ftp://publications.mit.edu/ai-publications/500-999/AIM-864.ps
| Don't take his suggestions too literally, but do allow the ideas to
| percolate in your head.
| -- 
| Henry Baker
| www/ftp directory URL:
| ftp://ftp.netcom.com/pub/hb/hbaker/home.html

-- Dwight