On 22.01.2006 00:41, Colin Putney wrote:
> On Jan 21, 2006, at 5:38 PM, Andreas Raab wrote:
> 
> 
>>I *really* need to work on my Occlumency skills ;-)
> 
> 
> Well, publishing Islands was a pretty big tip-off. :-)

Thank's for the pointer, I've found
  http://impara.de/pipermail/tweak/2005-February/000434.html
from Andreas, which gives a good overview.
Thereafter (I have not played with its code) Islands try to provide
transparent access to objects in other islands: there are no code
differences in sending messages to an object located (and created) in
the current or any other Island.

There are problems with Islands though, see
  http://heim.ifi.uio.no/~trygver/2005/babyuml/tweakComponents.pdf
.

> 
> I've been mulling this over from time to time as well. It occurred to  
> me that one of the big drawbacks to message passing concurrency is  
> that Islands are much heavier than Processes. That would be even more  
> true if they were based on native threads or OS processes.
> 

> But, since we're talking about substantially modifying the VM, there  
> might be a way to avoid bloat. If we allowed class pointers to be  
> distant as well, we could have a system that created relatively small  
> Islands, starting with a single object. Islands would grow as new  
> objects were created inside them, 

> message arguments were passed by value,
Also results for many cases!
Far references to objects located at other hosts raise problems (that
doesn't mean, that they are not wanted).

> or CompiledMethods, Classes, literals and the like were pulled  
> into the Island spoon-style.

This seems to me the main idea of Spoon: to start with a minimal image
and to load what is needed for execution on demand.

> 
> This kind of a system would require rethinking the way the  
> development environment works, system changes are managed etc, since  
> there isn't really a clearly-delimited "image" anymore. It would be  
> interesting to see what kind of system emerged from that.

Combining Spoon with concepts (not the implementation AFAICS) from
Islands as tools for tracking the states of the distributed systems and
their connections (!) could be the next steps. This is much work though.


Regards,
Stephan

PS: Croquet?

> 
> Colin
> 
> 

-- 
Stephan Rudlof (sr at evolgo.de)
   "Genius doesn't work on an assembly line basis.
    You can't simply say, 'Today I will be brilliant.'"
    -- Kirk, "The Ultimate Computer", stardate 4731.3