I have a few functions written in C for a game project. These functions get called quite a lot (about 2000-4000 times per second). The functions are written in C for raw speed.
Now, the easiest way for me to include these functions into Python is to use ctypes. The alternative is to write a C extension to Python around these functions (which takes quite a bit of extra effort). So I wondered, not including the initial loading of the DLL, how big is the overhead of ctypes?
I'm using Python 2.7 (the standard CPython release), and I do not want to use an external library like Cython.
I know this question has been asked before, but I haven't seen much information about the performance comparison between the two options.
I've compared the performance of a C extension vs. a ctypes wrapper. In my particular test, the difference was about 250x. There were multiple calls into the C library so the ctypes wrapper was also executing Python code. The running time for the C library was very short which made the extra overhead for Python code even more significant. So the ratio will likely be different for you but was significant in my case.