Hi Eric, You're right - 2.2.1 is long-in-the-tooth but it's the version shipped in the Raspian distribution. I'll see if I can get the RPIF to upgrade the distro to PyPy 2.6 and I'll give it a go myself too.
Andy -----Original Message----- From: Eric Driggers [mailto:admall...@gmail.com] Sent: 01 July 2015 17:16 To: Andy Baker Cc: PyPy Developer Mailing List Subject: Re: [pypy-dev] pypy 2.2.1 performance on Raspian 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
