std.parallelism equivalents for posix fork and multi-machine processing

[Laeeth Isharc via Digitalmars-d]

On Thursday, 14 May 2015 at 10:15:48 UTC, Daniel Murphy wrote:
> "Laeeth Isharc"  wrote in message 
> news:ejbhesbstgazkxnpvqsl at forum.dlang.org...
>
>> Is there value to having equivalents to the std.parallelism 
>> approach that works with processes rather than threads, and 
>> makes it easy to manage tasks over multiple machines?
>>
>> I took a look at std.parallelism and it's beyond what I can do 
>> for now. But it seems like this might be a useful project, and 
>> not one of unmanageable difficulty...
>
> Yes, there is enormous value.  It's just waiting for someone to 
> do it.

To start the process off (because small beginnings are better 
than no beginning): what are the key features of processes vs 
threads one would need to bear in mind when designing such a 
thing?  Because I spent the past couple of decades in a different 
field, multiprocessing passed me by, so I am only now slowly 
catching up.