for what is worth, you not gonna get better performance from C extensions between PyPy 2.2 and 2.6
On Wed, Jul 1, 2015 at 6:55 PM, Andy Baker <a...@pistuffing.co.uk> wrote: > 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 _______________________________________________ pypy-dev mailing list pypy-dev@python.org https://mail.python.org/mailman/listinfo/pypy-dev
