[Python-Dev] Benchmarks: Comparison between Python 2.7 and Python 3.6 performance

[Victor Stinner]

2016-11-07 20:20 GMT+01:00 Guido van Rossum <guido at python.org>:
> Re:
> https://speed.python.org/timeline/#/?exe=4&ben=python_startup&env=1&revs=50&equid=off&quarts=on&extr=on
>
> That's suspiciously close to the core sprint. Since the -S time stayed
> roughly the same I suspect that either a new module was added to the startup
> sequence or one of the (too many) modules already involved grew a lot. My
> money is on a new module. Using `python -v -c pass` on a Python built from
> the Sept. 9 tree and one built from Sept. 15, it shouldn't be too hard to
> figure out which new module(s).

I identified the regression, I created:

   http://bugs.python.org/issue28637

It's a regression caused by:

   https://hg.python.org/cpython/rev/223731925d06/
   http://bugs.python.org/issue28082

The change added "import enum" in Lib/re.py. I propose to revert this
change for now, and discuss later a solution which doesn't impact
performances.

It's nice to see that my work of performance was useful to catch a
performance regression.

Victor