Add a note on PyPy

Author: vstinner

README.rst

@@ -24,4 +24,8 @@ possible.
   (source code, issues)
 * `Download pyperformance on PyPI <https://pypi.python.org/pypi/pyperformance>`_
 
+pyperformance is not tuned for PyPy yet: use the `PyPy benchmarks project
+<https://foss.heptapod.net/pypy/benchmarks>`_ instead to measure PyPy
+performances.
+
 pyperformance is distributed under the MIT license.

doc/index.rst

@@ -43,6 +43,10 @@ See also the `Python speed mailing list
 <https://mail.python.org/mailman/listinfo/speed>`_ and the `Python pyperf module
 <http://pyperf.readthedocs.io/>`_ (used by pyperformance).
 
+pyperformance is not tuned for PyPy yet: use the `PyPy benchmarks project
+<https://foss.heptapod.net/pypy/benchmarks>`_ instead to measure PyPy
+performances.
+
 Image generated by bm_raytrace (pure Python raytrace):
 
 .. image:: images/bm_raytrace.jpg