pyfastcopy

pyfastcopy

|Latest version| |Tests status| |Coverage| |Supported Python versions|

pyfastcopy is a simple Python module that monkey patches the shutil.copyfile function of Python standard library to internally use the sendfile system call.

It can provide important performance improvements for large file copy (typically 30-40%). See the performance section <#performance>__ for some numbers.

Because shutil.copyfile is used by other fonctions in the shutil module, the following functions also automatically benefit from the performance boost:

• shutil.copy
• shutil.copy2
• shutil.copytree

If sendfile is not available on your system or fails, the classic, slower chunk file copy is used, so there is no downside to using this module.

For more information, see my proposed patch <https://bugs.python.org/issue25156>__ for Python.

Performance

Tests were done copying files (source and destination) on a tmpfs <https://en.wikipedia.org/wiki/Tmpfs>__ filesystem, so that no slowdown related to hard drive or SSD storage occurs. Test files were generated with pseudo random data using frandom <http://www.billauer.co.il/frandom.html>__.

See benchmark.py <https://github.com/desbma/pyfastcopy/blob/master/benchmark.py>__ for details about the test procedure and how the following graphs were generated.

Python 3.4: |graph1| |graph2| |graph3|

Python 3.6: |graph4| |graph5| |graph6|

These tests show a 30-50% performance improvement of shutil.copyfile compared to stock Python.

Usage

Just import the module:

::

import pyfastcopy

And then use the patched shutil.copyfile as usual:

::

shutil.copyfile(src, dst)

The sendfile system call does not exist on Windows, so importing this module will have no effect.

Installation

From PyPI (with PIP)

1. If you don't already have it, `install
   pip <https://pip.pypa.io/en/stable/installing/>`__ for Python 3 (not
   needed if you are using Python >= 3.4)
2. Install pyfastcopy: ``pip3 install pyfastcopy``
3. Enjoy fast copy when using ``shutil.copyfile``, ``shutil.copy``,
   ``shutil.copy2`` or ``shutil.copytree``

From source
~~~~~~~~~~~

1. If you don't already have it, `install
   setuptools <https://pypi.python.org/pypi/setuptools#installation-instructions>`__
   for Python 3
2. Clone this repository:
   ``git clone https://github.com/desbma/pyfastcopy``
3. Install pyfastcopy: ``python3 setup.py install``
4. Enjoy fast copy when using ``shutil.copyfile``, ``shutil.copy``,
   ``shutil.copy2`` or ``shutil.copytree``

License
-------

Python Software Foundation License

.. |Latest version| image:: https://img.shields.io/pypi/v/pyfastcopy.svg?style=flat
   :target: https://pypi.python.org/pypi/pyfastcopy/
.. |Tests status| image:: https://img.shields.io/travis/desbma/pyfastcopy/master.svg?label=tests&style=flat
   :target: https://travis-ci.org/desbma/pyfastcopy
.. |Coverage| image:: https://img.shields.io/coveralls/desbma/pyfastcopy/master.svg?style=flat
   :target: https://coveralls.io/github/desbma/pyfastcopy?branch=master
.. |Supported Python versions| image:: https://img.shields.io/pypi/pyversions/pyfastcopy.svg?style=flat
   :target: https://pypi.python.org/pypi/pyfastcopy/
.. |graph1| image:: https://i.imgur.com/fbKbKgmt.png
   :target: https://i.imgur.com/fbKbKgm.png
.. |graph2| image:: https://i.imgur.com/Cnrwi2Yt.png
   :target: https://i.imgur.com/Cnrwi2Y.png
.. |graph3| image:: https://i.imgur.com/B3GDWFrt.png
   :target: https://i.imgur.com/B3GDWFr.png
.. |graph4| image:: https://i.imgur.com/5lnETSCt.png
   :target: https://i.imgur.com/5lnETSC.png
.. |graph5| image:: https://i.imgur.com/YsBWYsxt.png
   :target: https://i.imgur.com/YsBWYsx.png
.. |graph6| image:: https://i.imgur.com/k32LSbCt.png
   :target: https://i.imgur.com/k32LSbC.png