[link|http://www.python.org/ftp/python/contrib-09-Dec-1999/System/threading.README|http://www.python.or.../threading.README]
But removing the GIL slows down Python's speed on single CPU machines. What I'd like to see is either a) a compilation switch that incorporates the patches if you are going to run on SMP or b) a run-time switch that does the same.
The alternative is to just use cross-process communication and multiple Python processes, such as Twisted does.