Thread performance

[Moe A]

I'm writing a multi-threaded app in python that uses pygtk..and
obviously the performance of subroutines invoked from a thread rather
than from a GUI callback leave something to be desired.  i cant
implement a simple lock system because most of the threads are started
from the various modules i'm using.  so is there some way to
commandeer the majority of processing power from one of the threads
without making the gui unresponsive?