With the release of Python 3.8, this is the first time a Python 3.X version clearly beats Python 2.7, when running a speed testing script I wrote about a decade ago.

This is not a script aims to compare every function aspect of different versions of Python, it's written because I developed a pure Python ODBC module (pypyodbc), and I was very curious how bad, or fast, this module run on different implementations of Python, including: CPython 2.X, CPython 3.X, PyPy and even IronPython.

While on all of the above-mentioned interpreters, the pure python module could run normally, the performance rank was always being: PyPy > CPython 2.7 > CPython 3.X > IronPython

Some interesting findings are:

• PyPy is obviously the fastest, and one can see it’s always speeding up seconds by seconds when running the script.

• Surprisingly, IronPython was not very slow in my case, it’s about 80% performance of CPython 2.7, but with a quite noticeable startup time.

• Till Python 3.8, CPython 3.X was slower than Python 2.7.

Since Python 3.8 was released:

PyPy > CPython 3.8 > CPython 2.7 >= CPython 3.7 > IronPython

It’s finally a litter bit faster than Python 2.7. Consider that for compatiblity purpose, the testing script and the module itself is written in a way both 2.X and 3.X could run, but more friendly to Python 2.7, the performance of 3.x interpreter should be even better if codes are written in 3.x syntax.

update Python 3.9

Python 3.9, is a bit slower than Python 3.8, but still a bit faster than Python 2.7

PyPy > CPython 3.8 > CPython 3.9 > CPython 2.7 >= CPython 3.7 > IronPython

PyPy Total time: 42.5599999428 Python39 Total time: 53.853275537490845 Python38 Total time: 52.05243992805481 Python27 Total time: 53.9089999199 Python37 Total time: 57.95293974876404 IronPython Total time: 125.170227051