Re: For the AdaOS folks

[Nick Roberts <nick.roberts@acm.org>]

Wes Groleau <groleau+news@freeshell.org> wrote:

> or anyone else with similar ambitions.
> 
> Read "Kill the operating System" page 32 of September 2003 Technology
> Review
> 
> Not a prescription, but something to think about.

It's interesting that Garfinkel's comments correspond to many ideas that I
have had -- some in a vaguer form than others -- during my musings on OS
design.

One of the biggest challenges is to design an OS that works in a new and
better way, and yet is still capable of leveraging the power of an existing
software base.

One of the reasons, perhaps the biggest reason, why I decided on using a
microkernel was for security. I read the 'orange book' (the TCSEC) and
others which described how the world of computer science (especially within
governemntal and military sectors in the USA and the UK) foresaw the
evolution of computer technology. Remember that this is early 1990s, before
the domination of Microsoft. The overwhelming consensus was on a microkernel
based design, because this allowed the 'trusted computing base' (TCB) -- the
part of the overall system's software that had to be trusted not to subvert
security -- to be minimised.

The consensus was also on a 'fully distributed' system -- a network of
computers (always termed 'workstations' regardless of whether they had
screens, keyboards, etc.) that operated exactly like a single big computer,
from the point of view of normal users -- and so AdaOS is a
microkernel-based, fully distributed design.

However, I intend to design the microkernel so that it compromises on
minimality (unlike some other microkernel designs) to achieve reasonable
efficiency (whilst removing much of unnecessary detritus that bogged down
experimental microkernels), and I intend to ensure that administrative
division of the network is fully supported, as well as network partioning
robustness (if some workstations go down, the rest still work).

For a very long time, IBM mainframes have supported (very efficient)
programmatic access to a system database, as an alternative to file-based
data storage. I would like provide both forms of storage in AdaOS, in
addition to 'persistent objects' in some form.

At the moment, the place where we would like people to discuss AdaOS issues
(or anything at all related to OS design) is:

   http://adaos.multiply.com/

You have to register with Multiply, but that is a very simple process (and
you seem to be protected from junk mail etc.).

-- 
Nick Roberts