cthreading

========== cthreading

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

Status: |travis|

.. |travis| image:: https://travis-ci.org/nirs/cthreading.svg?branch=master :alt: Travis-CI Build Status :target: https://travis-ci.org/nirs/cthreading

Performance

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 whispers.py -m cthreading
real    0m2.664s
user    0m2.965s
sys     0m0.808s

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

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

$ time python whispers.py -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 https://github.com/nirs/cthreading/wiki/performance.

Usage

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
cthreading.monkeypatch()

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

Tested platforms

x86_64

• 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)

POWER8E

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

Hacking

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::

make

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

make regrtest

Check the Makefile for more info.

Similar projects

• pthreading <https://github.com/oVirt/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.