Introducing Lua nodes

[Marc Balmer <marc@...>]

Lua nodes is a "different" way to execute Lua code.  It combines three 
existing technologies:  Lua, POSIX threads, and, 0MQ (zeromq.orq).  Lua 
nodes comes as a binary, called "node", which takes a filename of a Lua 
program as argument.  This Lua program is meant to "orchestrate" a 
network of Nodes.

This program can thus create "nodes" using the "node" module. Nodes are 
independent Lua states running in their own thread.  Nodes can 
communicate using 0MQ (zeromq) message queues.  The Lua states run truly 
in parallel and use all available CPU cores.  This has nothing to do 
with Lua coroutines (which are still available to each Lua state).

Nodes can communicate between threads in the same process, processes on 
the same machine, or, processes on different machines by using zeromq 
message queues.  Lua nodes allow for full distributed/parallel 
processing, using a simple language, Lua.

A new Node (i.e. a Lua state running in its own thread) is created using 
node.create():

local n = node.create('worker.lua', 'bee', 42)

This will create a new thread with a new Lua state, running the chunk 
found in the file "worker.lua", passing the arguments "bee" and 42 in 
"..." to worker.lua.

Nodes can use the "zmq" module to communicate with each other.  So it is 
possible to run multiple independend Lua threads in one process and have 
them communicate with each other, or with Nodes in differents processes 
on the same machine, or with Nodes running on a remote machines.

Comments, suggestions, and, ideas welcome.