Python 3 at Facebook

Posted Jul 3, 2018 17:55 UTC (Tue) by Cyberax (✭ supporter ✭, #52523)
In reply to: Python 3 at Facebook by anselm
Parent article: Python 3 at Facebook

It can go either way. Py3 in general used to be slower than Py2: https://stackoverflow.com/questions/37052139/string-perfo... or https://www.raspberrypi.org/forums/viewtopic.php?t=183829 It's getting better, but it's still not that great.

I did several migrations and sometimes we actually got significant speed improvements. Not because of 2->3 switch itself, but because people went through the codebase and fixed stuff like the use of .items() instead of .iteritems().

Python 3 at Facebook

Posted Jul 4, 2018 0:32 UTC (Wed) by anselm (subscriber, #2796) [Link]

It probably depends on the use case but there has been considerable optimisation work done in recent Python versions (the web pages you cited mostly talk about Python 3.4, which from an optimisataion POV is ancient history). There will be even more improvement in the future but we're now at a point where a fear of performance regressions compared to Python 2.7 shouldn't keep one from moving to Python 3.6 or 3.7.

Python 3 at Facebook

Posted Jul 4, 2018 5:23 UTC (Wed) by daniel (guest, #3181) [Link]

Python2 and Python3 are both pathetically slow, because efficiency is not ingrained in the project culture. But they are better than Bash, that is the best I can say about that. Python stewards consciously choose to pigeonhole Python as a scripting language for no discernible reason. My advice for language learners these days: start with Python to get the idea, then move on quickly to Go.