Archive for Februar, 2010

Cython C++ wrapping benchmarks

Sonntag, Februar 21st, 2010

A couple of weeks ago, I found the C++ wrapping benchmarks on the PyBindGen homepage. The author posted a short blog intro about them. I wondered why Cython wasn’t used as a comparison at the time, until I found out that the wrapper was rather tricky to write in Cython back then due to the lack of good C++ language support (especially for overloaded functions/methods).

Cython has improved its C++ support considerably since then, due to the work of Danilo Freitas and Robert Bradshaw, which was recently merged into mainline and is now scheduled for Cython 0.13. This allowed me to provide a simple and short implementation of the wrapper module used in the above benchmark. The timings are rather unsurprising: Cython beats them all. This is mainly due to the fact that Cython uses highly optimised argument handling code, which greatly reduces the call overhead of a wrapper.

I also like how readable the Cython wrapper code is, especially compared to the rather unwieldy PyBindGen implementation. Obviously, this comparison is a bit unfair because Cython is a programming language with an optimising compiler, whereas the other tools are simply glue code generators. But the benchmark results certainly speak volumes.