goless Benchmarks

I benchmarked how goless performs under different backends (goless is a library that provides a Go-like concurrency model for Python, on top of stackless, PyPy, or gevent). Here are the results, also available on the goless readthedocs page:

Platform Backend   Benchmark      Time
======== ========= ============== =======
PyPy     stackless chan_async     0.08400
CPython  stackless chan_async     0.18000
PyPy     gevent    chan_async     0.46800
CPython  gevent    chan_async     1.32000
~~~~~~~~ ~~~~~~~~~ ~~~~~~~~~~~~~~ ~~~~~~~
PyPy     stackless chan_buff      0.08000
CPython  stackless chan_buff      0.18000
PyPy     gevent    chan_buff      1.02000
CPython  gevent    chan_buff      1.26000
~~~~~~~~ ~~~~~~~~~ ~~~~~~~~~~~~~~ ~~~~~~~
PyPy     stackless chan_sync      0.04400
CPython  stackless chan_sync      0.18000
PyPy     gevent    chan_sync      0.44800
CPython  gevent    chan_sync      1.26000
~~~~~~~~ ~~~~~~~~~ ~~~~~~~~~~~~~~ ~~~~~~~
PyPy     stackless select         0.06000
CPython  stackless select         0.38000
PyPy     gevent    select         0.60400
CPython  gevent    select         1.94000
~~~~~~~~ ~~~~~~~~~ ~~~~~~~~~~~~~~ ~~~~~~~
PyPy     stackless select_default 0.00800
PyPy     gevent    select_default 0.01200
CPython  stackless select_default 0.19000
CPython  gevent    select_default 0.25000

The trends are that PyPy with its built-in stackless support is fastest, then Stackless Python (2-5x), then PyPy with gevent (5-10x), and finally CPython with gevent (15-30x).

Remember that these are benchmarks of goless itself; goless performance characteristics may be different in real applications. For example, if you have lots of C extensions, CPython/stackless may pull ahead due to stack switching.

If you’re using goless for anything, I’d love to get some benchmarks, and find out how it’s working, so please comment below, or create a GitHub issue.

Disclaimers: It’s possible that goless is inefficiently using gevent, but the backend-specific code is so simple I doubt it (see goless/goless/backends.py). These benchmarks are all done against Python 2.7. Also I am no benchmark master (especially with PyPy) so there may be problems, look over goless/benchmark.py for benchmark code. These were done mostly for curiosity.