Benevolent Dictatorship

Rainer Joswig
Sat, 21 Mar 1998 19:46:27 +0100

At 17:41 21.03.98 +0100, Rodrigo Ventura wrote:

>        Hum, I guess I considered myself humble enought to do not dare
>pointing a bug in the claimed "best CL system". I probably did
>something wrong.

But what?

> But as I was evaluating several CL systems, I simply
>passed on to the next one.

Without bug reports software will never improve. Without complaining
about software documentation, installation and usage instruction
software will never improve.

Currently there are not too much Lisp users and developers. Vendors
have some excellent systems. But on the free software side we are
not seeing too many Lisp applications (besides some University stuff)
that can be compared to existing C/Perl/whatever based software.

>From people here on this list, who are interested in having something
that does not exist (besides on some exotic platforms), I would
expect also that they are willing to contribute time (e.g. real lines of code and

>    Rainer> The trick to make CMU CL useable is to increase the heap and make
>    Rainer> GC occur less often. Applications will need more space but will
>    Rainer> GC less frequent. Adding a generational/ephemeral GC
>    Rainer> would get rid of this. Improve CMU CL!
>        Increase the heap size???? Well, when I did a "ps ux" I
>noticed that CMUCL was using about 22MB of virtual memory! 22MB!!!

Seems not too much for a CL system. Was it on a SPARC?

When I load MCL with my usual software I start it with
30 MB on my laptop. It can be used with 5 MB, though. 
Lispworks on my PC currently has (... looking ...) 46MB
after some usage.

I'm starting my Symbolics (Lisp based Genera is the OS)
with some 200-300 MB virtual memory. Sometimes when
I'm doing some log analysis my Lisp Machine gets 600 MB VM.
Doing a full GC then takes a long time (30 minutes and more).
But usually you don't need it very often (once a week?),
due to the other GC mechanism available. The basic Symbolics
Genera image file is around 50 MB on disk.

The machines from 1990 with the Ivory chip (comparable in many
ways to a 40-50 Mhz 68030) were very usable. A Lisp OS
on todays machines would be very^h^h^h^h^hextremely fast. The all in Lisp
approach makes it unnecessary to have too many software
layers (-> interpreting/translating/converting) which are slowing
things down.

>There were times when a PC with 10MB hard drive was a luxury!

When was it? Before or after the stone age? ;-)

Have you looked lately how much disk space current development
environments need (Visual C++, Codewarrior, ...)?
If you are a developer for Oracle they'll send you a
package of 50+ CDROMs (removing the duplicates for
different platforms brings it down to 30+).

The Genera OS from Symbolics is really tiny compared to
those systems. An image, much of the source
code of the OS, and the documentation would spread
to (just a guess), say, 150 MB.

My Symbolics 3640 from 1985 got in 1988 a 600 MB drive!!! We are
living ten years later. It is hard to get drives with less than 2 GB.
Typical laptops have disks between 2-5 GB.

If you want a reasonable Lisp environment or a usable Lisp OS
with GC and all the fun stuff (GUI, mailer, command interpreter,
documentation, browsers, editor, backup software, web server,
web browser, software distribution system, versioned file
system, etc.) be prepared that you will need more than
22 MB.

Actually I don't care that much about space nowadays.
Our own time is much more valuable than a few MB of RAM chips.