Ned Konz wrote:
> 
> Lex Spoon wrote:
> 
> > For a longer discussion of this topic check out:
> >
> >         http://www.sun.com/research/technical-reports/1994/abstract-29.html
> >
> > (I was so happy to run into this writeup, since it's an argument I
> > find myself alone in a lot.)

Lex has been hanging out with the wrong people I think. ;-) Most
distributed systems people are very aware of the differences pointed out
in this paper. Also, partial failures have been said to be one of the
major issues in distributed systems.

> I read the article. Some of what it describes as problems -- for instance,
> the memory space differences -- don't exist in the same way in Squeak.
> We only pass around object references, never pointers to raw address space.

Yes, but, I feel that the programmer *should* be aware that he's passing
a reference to a remote VM. (Not that this should be harder than, or
even different from, passing a local reference, though) The thing is, in
Smalltalk we tend to pass a *lot* of messages around. Add to this the
high latency of passing a message over the network, and the system slows
down considerably. If the programmer is aware of this he/she can keep it
in mind while designing, and try to optimise. 

> And I don't agree with their argument that concurrency in distributed systems
> is fundamentally different than in a multi-threaded program in general (that
> is, once you've taken care of the partial failure problem).

Once you've taken care of a major issue, the rest becomes 'easy' ;-)

> But it made some good points.

I agree. :-)

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"You are more than the sum       Johan Fabry - Johan.Fabry at vub.ac.be
 of what you consume.            Vrije Universiteit Brussel
 Desire is not an occupation."   Programming Technology Lab, Room 10F709
  -- KMFDM                       Pleinlaan 2, 1050 Brussels, Belgium