Hi Patrick, Thanks for the links. I looked briefly at the Twisted reference, but since I do not speak python, it was a hard going. :) I will put more effort into it soon. Best, Don --- Patrick M�zard <pmezard@gmail.com> wrote:

You should take a look at the python Twisted framework <http://twistedmatrix.com/>. There are performance issues in python with threads because of the Global Interpreter Lock (GIL). The framework is a workaround, performing every task in an asynchronous way from a single thread. The design of the Defer class is interesting and is the key of asychronous tasks control flows

(<http://twistedmatrix.com/projects/core/documentation/howto/defer.html>).

By the way, there were and will be lengthy discussions about which approach is the "best" to build scalable concurrent programs. I think that multithreading and event-driven programming were proven to be equivalent from a theorical point of view, but there real differences in implementation. You could read this one and many items from its bibliography too:

<http://capriccio.cs.berkeley.edu/pubs/threads-hotos-2003.pdf> (The Capriccio project was really interesting too, on the paper. I do not know where they are now).

Patrick M�zard

__________________________________ Do you Yahoo!? Yahoo! Sports - Sign up for Fantasy Baseball. http://baseball.fantasysports.yahoo.com/