multiprocessing vs thread performance

[Roy Smith]

In article <mailman.6337.1230563873.3487.python-list at python.org>,
 Christian Heimes <lists at cheimes.de> wrote:

> You have missed an important point. A well designed application does
> neither create so many threads nor processes. The creation of a thread
> or forking of a process is an expensive operation. You should use a pool
> of threads or processes.

It's worth noting that forking a new process is usually a much more 
expensive operation than creating a thread.  Not that I would want to 
create 100,000 of either!

Not everybody realizes it, but threads eat up a fair chunk of memory (you 
get one stack per thread, which means you need to allocate a hunk of memory 
for each stack).  I did a quick look around; 256k seems like a common 
default stack size.  1 meg wouldn't be unheard of.