[erlang-questions] : Subtle behaviour of Erlang scheduler

[KatolaZ]

On Tue, May 29, 2007 at 12:02:48PM +0200, Kenneth Lundin wrote:
> >
> >But the last two mails, which suddenly close the Pandora Vase we
> >opened looking a little deep inside the process scheduler, simply
> >explain that Erlang developers (or at least Ericsson OTP group), has
> >little or no interest on having a real robust, affordable,
> >distributed, secure and real-time platform.
> 
> Erlang was originally designed to be an efficient development environment 
> for
> rubust, parallel possibly distributed control systems with soft
> real-time requirements. Erlang fulfill that purpose very well.
> The erlang distribution protocol is designed to be used in a local
> network and lacks many security mechanisms that might be needed if
> used over the public internet.
> (If that is what you mean with secure?).
> 
> Supporting 'hard' real-time is a completely different thing which would 
> require
> a major redesign of the virtual machine possibly also many new
> primitives and changes to language.

Thank you very much, Kenneth. This is the answer I expected from the
OTP group: a really *technical* explanation, not a *commercial* one
:-)

I mostly agree with you: implementing hard real-time in Erlang would
require a non-trivial effort, and I understand that it is not easy to
face all problems related to hard real-time support: this would
probably require a re-implementation of the Erlang scheduler, or at
least a deep review of process priority system.

But I'm still convinced that it could be interesting to try. And I
suppose we'll try to do something in that direction. :-)

Best Regards

Enzo

-- 
[ Enzo Nicosia aka KatolaZ --- GLUG Catania -- Freaknet Medialab ]
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