Re: Ada OS : towards an Ada Micro-kernel

[antoine terrienne <antoine.terrienne@openwide.fr>]

OPERA wrote:
> Hello,
> 
> I have seen many discussions about using a micro-kernel such as L4 as a
> foundation for
> a new OS for ADA. I believe this can be a great idea, I would like to
> suggest some ideas
> about that :
> 
  *skip*
> But, for me, L4 primitives are not fully compatible with ADA
> requirements : in particular,
> they can't be used to implement multiple "select alternatives". As an
> example, we need new primitives
> that allow something like : Message_Accept( "list of entries").
> 

That's right. L4 provides only tasking and ipc. anything like
memory managing, mutexes, scheduling, IRQ managing, dynamic
linking etc.. should be provided by servers on top of L4

> Therefore, I believe that the creation of a new micro-kernel must follow
> two steps :
> 1. identify what primitives ADA needs, and their level of abstraction
> 2. try to implement them efficiency on a given machine (= to make a
> micro-kernel), by
> reusing if needed existing micro-kernel such as L4 or Hurd.
> 
> Any comment on this would be greatly appreciated !
> 
> Vincent Diemuunsch
> 

humm.. hurd is not a microkernel it is a collection of servers running
on top of gnumach. But mach is an old microkernel with low efficiency.
Hurd will be ported on L4 v4 (Pistachio) is the distant future as L4 is
the new generation microkernel (mush more efficient as it is mush more
minimal). for info on hurd on L4 see :
http://kerneltrap.org/node.php?id=157

For information there is a project (ADX) to build such an operating
system. Well for now there is noting done yet I stil work on the
specifications. http://antoine.terrienne.free.fr/adx/index.html

If you want to discuss about desinging an Ada os on top of L4 you are
also wellcome on the ADX mailing list :
http://fr.groups.yahoo.com/group/projet-adx/