Mythical small kernel images?

Stephane Ducasse ducasse at
Mon Feb 10 18:51:01 UTC 2003

By the way you may be interested to read the following :)

From: Lars Bak <larsbak at>
Date: Tue Jan 28, 2003  9:56:12 AM Europe/Zurich
To: Stephane Ducasse <ducasse at>
Subject: Re: Smalltalk VM

Hi Stephane,
  it is true we have a Smalltalk system that runs on the bare metal. VM 
+ Basic libraries + TCP/IP stack is running
  in 128Kb of RAM. To ensure performance of blocks we have made a simple 
restriction. Blocks are LIFO (like
  Pascal procedures) and they cannot be assigned to object fields. 
Interestingly enough, this restriction has not been
  an obstacle what so ever. The advantage is block contexts can be stack 
allocated and thereby reduce pressure
  on the garbage collector.

  Unfortunately, we are an early startup company and do not have 
material we can send you.
Thanks for the interest,
  Lars Bak

P.S. I gave a talk at Aarhus University a month ago about our system. 
Please find the abstract attached.


			   Lars Bak, OOVM:

		       Robust Embedded Software

Developing  software for  embedded  systems has  until  now been  very
static.  Source code,  written in  C, is  compiled and  linked  on the
development  platform and  the resulting  binary image  is transferred
onto  the device.  In an  industry where  robustness is  paramount and
dynamic software updates are required this is simply not good enough.
This presentation will describe  a new approach to developing software
for  embedded devices. At  the bottom  of the  software stack  we have
replaced the operating system with an object-oriented virtual machine.
Scheduler,  interrupt handlers,  device drivers,  networking  code and
application software are executing on  top of this virtual machine. We
will discuss  some of the  design decisions behind this  dynamic, lean
and  mean system for  embedded devices.  The complete  system occupies
less than 128Kb.  This approach solves many of  the existing problems,
allowing dynamic software updates and full serviceability.

We  will  conclude  with  a  demonstration  of  the  OOVM  programming

On Monday, February 10, 2003, at 02:34 PM, goran.hultgren at 

> Hi all!
> A while ago around OOPSLA 2002 I think there was some talk about two
> impressive achievements - one really tiny kernel image by Dan Ingalls
> weighing in at a mere 246kb (if my memory serves) and one by Andreas
> Raab just a teeny bit larger.
> Since I just got a silly challenge from my brother to whip up a small
> networking non-UI trivial app I thought it would have been cool to both
> use a minimal image and perhaps even go to the length of making a
> minimal VM for it. :-) Why? Well, because it could be cool to demo for
> all those Java-dudes demanding a ~9Mb JRE download. :-)
> Perhaps Andreas or Dan or anyone else who knows anything could give us 
> a
> status report?
> regards, Göran
Prof. Dr. Stéphane DUCASSE (ducasse at
  "if you knew today was your last day on earth, what would you do
  different? ... especially if, by doing something different, today
  might not be your last day on earth" Calvin&Hobbes

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