Unless I am missunderstanding, isn't pypy 2.2.1 rather old? Have you tried a more up-to-date version first? (I seem to see current stable is 2.6.0 and nightly is 2.7.0-alpha0) My memory is that between 2.3 and 2.4 there was some armhf work done, and that between 2.3 and 2.5 a whole pile of stuff was done that improved pypy -> C (mostly to help cffi, but helped CAPI and ctypes a bit too IIRC)
It is still probably a good idea to see about using cffi (and you can use cffi on cpython as well!) but low hanging fruit and all that :D On Wed, Jul 1, 2015 at 8:38 AM, Andy Baker <a...@pistuffing.co.uk> wrote: > Hi Armin, > > Thanks for the insight. I'll have a look in more detail to port the 'C' > modules away from the CPython C API to CFFI. The performance tests I was > doing were about 10000 loops of reading sensors (the Cpython C API > libraries) along with 1000 loops of arithmatic / trigonometry processing the > sensor data. I guess the "only 2.5 times slower" is the balance between the > improved math(s) performance and the reduced sensor performance. > > Thanks, > > Andy > > -----Original Message----- > From: armin.r...@gmail.com [mailto:armin.r...@gmail.com] On Behalf Of Armin > Rigo > Sent: 01 July 2015 15:33 > To: Andy Baker > Cc: Cory Benfield; PyPy Developer Mailing List > Subject: Re: [pypy-dev] pypy 2.2.1 performance on Raspian > > Hi Andy, > > Using the CPython C API is very slow on PyPy. If your program is mostly > spending its time issuing calls via the CPython C API, then getting "only" > 2.5x slower is already good :-/ CFFI is much, much faster on PyPy. If you > don't want to rewrite your CPython C API modules (even though you said they > are very thin layer, which means it shouldn't be much work), then you're > better off with CPython. > > Additionally, make sure to read > http://pypy.readthedocs.org/en/latest/faq.html#how-fast-is-pypy and to > multiply the time estimates given there by 5 or 10: Raspberry Pi is much > slower than desktop PCs. > > > A bientôt, > > Armin. > > _______________________________________________ > pypy-dev mailing list > pypy-dev@python.org > https://mail.python.org/mailman/listinfo/pypy-dev _______________________________________________ pypy-dev mailing list pypy-dev@python.org https://mail.python.org/mailman/listinfo/pypy-dev
