[Twisted-Python] Throttling outgoing client requests

[David E. Konerding]

Hi,

I am writing a client usign Twisted that makes a lot of XMLRPC requests 
simultaneously (using twisted.web.xmlrpc.Proxy).  There are a bunch of 
them, all to the same site,
and when I run on MacOSX, I start getting bind errors-- I think OS X 
must have more restricted outgoing network connections that the linux
box I normally work on.

My goal is to throttle the number of outgoing requests.  I could do this 
by submitting just one request at a time, and having a deferred callback
registered such that when the request completes (successfully or not) 
the next request is submitting.  But this sort of code flow is pretty
contorted.  My other thought would be to just schedule all the calls 
with a callLater and a randomized delay for each call.  Again, not so clean.

Is there a 'clean' way to throttle back the number of ongoing client 
requests-- perhaps through the xmlrpc.Proxy itself, or through some pattern?

Dave