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