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Revision as of 23:00, 13 January 2011 by Dmalcolm (talk | contribs) (→‎Current status: (Alex Gaynor's work is on out-of-tree RPython code, not .c code))

PyPy Stack


Fedora 34 has an alternate Python 2 runtime and add-on module stack built using PyPy, an alternate implementation of the Python 2 language, featuring Just-in-Time compilation.


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Current status

  • Targeted release: Fedora 34
  • Last updated: 2011-01-13
  • Percentage of completion: 30%

pypy-1.4.1 is packaged within Fedora (see the package review)

Areas of uncertainty:

  • as of 1.4.1, support for .c extensions (using the CPython API) is still experimental (need to try some extensions and see what works)
  • 1.4.1 ships with a bytecode format similar to (but slightly different from) CPython 2.5.1. It's not yet clear to me what the anticipated rate of change to the bytecode format is. If we build out a collection of pure-python extensions in RPM form (e.g. a pypy-django.rpm), with .pyc files, we don't want to be constantly having to rebuild them all as the precise bytecode format changes (even if we e.g. ported PEP 3147, we still ought to rebuild the RPMs)

Detailed Description

PyPy is a python interpreter written in a subset of python. The interpreter can have better memory use than CPython and speed is closing in on Cpython. The JIT'd version is faster than CPython in many benchmarks.

It is growing the ability to load CPython extension modules.

This feature is exploring the idea of shipping PyPy, and the scope is not yet clear, be it:

  1. just the core interpreter, or
  2. sharing pure-Python add-on modules with the system Python (but with split bytecode files), or
  3. a full, independent Python stack, but with just pure-Python add-on modules, or
  4. a full, independent Python stack, with both pure-Python and machine-code extension modules

Benefit to Fedora


How To Test

User Experience


Contingency Plan


Release Notes

Comments and Discussion