Speed ===== CPython, the most commonly used implementation of Python, is slow for CPU bound tasks. `PyPy`_ is fast. .. todo:: Fill in stub for Speed comparisons Context ::::::: The GIL ------- `The GIL`_ (Global Interpreter Lock) is how Python allows multiple threads to operate at the same time. Python's memory management isn't entirely thread-safe, so the GIL is requried to prevents multiple threads from running the same Python code at once. David Beazley has a great `guide`_ on how the GIL operates. He also covers the `new GIL`_ in Python 3.2. His results show that maximizing performance in a Python application requires a strong understanding of the GIL, how it affects your specific application, how many cores you have, and where your application bottlenecks are. C Extentions ------------ The GIL ------- `Special care`_ must be taken when writing C extensions to make sure you register your threads with the interpreter. C Extentions :::::::::::: Cython ------ Pyrex ----- Shedskin? --------- Threading ::::::::: Threading --------- Spanwing Processes ------------------ Multiprocessing --------------- .. _`PyPy`: http://pypy.org .. _`The GIL`: http://wiki.python.org/moin/GlobalInterpreterLock .. _`guide`: http://www.dabeaz.com/python/UnderstandingGIL.pdf .. _`New GIL`: http://www.dabeaz.com/python/NewGIL.pdf .. _`Special care`: http://docs.python.org/c-api/init.html#threads