Re: concurrency research "hot" again?

[Matthew Jadud <mcj4@xxxxxxxxxx>]

Andrzej Lewandowski wrote:
> "If OS size is in  kilobytes.. " You are kidding, aren't you?... Or,
> maybe....  you are a PROFESSOR? This would explain everything...
>
> A.L.

>> also to elegant (small) OS constructs. If OS size is in
>> kilobytes, there's hope you can understand COMPLETELY what it
>> is doing, especially if the OS restricts itself to resource
>> loading and leaves run-time concurrency to applications.


To be fair, the Transterpreter provides a scheduler and runtime 
environment for programs compiled to the extended Transputer instruction 
set, and it runs in less than 10K on 16-bit devices. Compiled and 
stripped, it is 31K on Windows (as of yesterday). The core is only 
around 3KLoC, I think (although I haven't counted yesterday).

The question is: how much more work does the virtual machine need to do 
before you consider it an "OS". Process management? Memory management? 
Disk/file systems? Networking? Security? GUI? Drivers? We already hit 
two of those head-on in the runtime, and the rest can be written in a 
high-level language (eg. occam, occam-pi, or similar). Singularity is on 
the same track, and is only a few thousand lines of code longer.

So, perhaps it's you who is kidding? Or, perhaps we mean different 
things when we say "OS". You might mean something that is 1-5GB in size 
(installed) and crashes on a daily basis? That, of course, could be a 
definition of an OS...

Cheers,
Matt