Python performance myths and fairy tales
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Antonio Cuni, who is a longtime Python performance engineer and PyPy developer, gave a presentation at EuroPython 2025 about "Myths and fairy tales around Python performance" on the first day of the conference in Prague. As might be guessed from the title, he thinks that much of the conventional wisdom about Python performance is misleading at best. With lots of examples, he showed where the real problems that he sees lie. He has come to the conclusion that memory management will ultimately limit what can be done about Python performance, but he has an early-stage project called SPy that might be a way toward a super-fast Python.
He started by asking the audience to raise their hands if they thought "Python is slow or not fast enough"; lots of hands went up, which was rather different than when he gave the presentation at PyCon Italy, where almost no one raised their hand. "Very different audience", he said with a smile. He has been working on Python performance for many years, has talked with many Python developers, and heard some persistent myths, which he would like to try to dispel.
