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C implementation of Python 2 threading's Lock, RLock, and Condition

Project Description

cthreading implements Python 2 Lock, RLock, and Condition in C, speeding
up threads synchronization and decreasing cpu usage.

Status: |travis|

.. |travis| image::
:alt: Travis-CI Build Status


cthreading eliminates the overhead of `threading.RLock` and
`threading.Condition` which are implemented in pure Python in Python 2.
In particular, `threading.Condition` is implemented using polling. In
Python 3 `threading.Condition` is implemented without polling;
cthreading implements a similar design in C.

.. code-block::

$ time python -m cthreading
real 0m2.664s
user 0m2.965s
sys 0m0.808s

$ time python3
real 0m9.664s
user 0m8.949s
sys 0m1.812s

$ time python
real 0m14.914s
user 0m16.986s
sys 0m12.690s

$ time python -m pthreading
real 0m20.169s
user 0m23.062s
sys 0m17.022s

Your application is unlikely to have similar workload; do not expect
this improvement.

For more info see


Import cthreading before any other module and monkeypatch the thread and
threading modules. From this point, threading.Lock, threading.RLock, and
threading.Condition are using cthreading.

.. code-block:: python

import cthreading

Note: cthreading will raise RuntimeError if the threading module was
imported before `cthreading.monkeypatch()` is called.

Tested platforms


- Fedora 22 / Python 2.7.10
- RHEL 7.2 / Python 2.7.5
- RHEL 7.2 / Python 2.7.10+ (upstream)
- RHEL 7.1 / Python 2.7.5
- RHEL 6.7 / Python-2.6.6
- Ubuntu 14.04 Server / Python 2.7.6
- Ubuntu 12.04 Server / Python 2.7.3 (python regression tests not available)
- Ubuntu 12.04 / Python 2.6.9 (Travis container)
- Ubuntu 12.04 / Python 2.7.9 (Travis container)


- RHEL 7.2 / Python 2.7.5
- RHEL 7.2 / Python 2.7.10+ (upstream)


For rpm based distributions::

yum install python-devel python-test

For deb based distributions::

apt-get install python-dev libpython2.7-testsuite

Installing Python packages::

pip install pytest pytest-timeout yappi==0.93

Building and running the quick tests::


Before submitting patches, run the Python regression tests suite::

make regrtest

Check the `Makefile` for more info.

Similar projects

- `pthreading <>`_ - uses
pthread_mutex and pthread_cond apis directly via ctypes. This
introduces undefined behavior and actually slower and increases cpu
usage in most cases compared to the original Python implementation.
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File Name & Checksum SHA256 Checksum Help Version File Type Upload Date
cthreading-0.3.tar.gz (18.7 kB) Copy SHA256 Checksum SHA256 Source Nov 2, 2015

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