Ah! Ok, I've noted array.array (along with running bigger tests to check for JIT warm-up overheads). Hopefully I'll get some more time in a few weeks to play with variants. Cheers! i.
On 25 July 2011 10:08, Maciej Fijalkowski <fij...@gmail.com> wrote: > On Mon, Jul 25, 2011 at 11:00 AM, Ian Ozsvald <i...@ianozsvald.com> wrote: >> Dear all, I've published v0.2 of my High Performance Python tutorial >> write-up from the session I ran at EuroPython: >> http://ianozsvald.com/2011/07/25/high-performance-python-tutorial-v0-2-from-europython-2011/ >> >> Antonio - you asked earlier if the 'expanded math' version of the >> Mandelbrot solver (using doubles rather than complex numbers) would be >> faster - I've timed it and it is a bit faster with a nightly build of >> PyPy, but nowhere near as fast at ShedSkin's generated C output >> (details below). >> >> Maciej - thanks for pointing me at the numpy module. I've added a tiny >> section showing numpy in PyPy but I haven't converted the Mandelbrot >> solver to use it (even finishing v0.2 took longer than I'd thought). >> I'm hoping that some more exposure in the report might bring in more >> volunteers from outside. >> >> Here's a clip from the report in the PyPy section: >> "By running pypy pure_python.py 1000 1000 on my MacBook it takes 5.9 >> seconds, running pypy pure_python_2.py 1000 1000 takes 4.9 seconds. >> (Ian - the only difference with pure_python_2.py is that local >> dereferences in the tight loop are moved outside the loop, causing >> fewer dereference operations) >> >> As an additional test (not shown in the graphs) I ran pypy >> shedskin2.py 1000 1000 which runs the expanded math version of the >> shedskin variant below (this replaces complex numbers with floats and >> expands abs to avoid the square root). The shedskin2.py result takes >> 3.2 seconds (which is still much slower than the 0.4s version compiled >> using shedskin)." >> >> The pure_python src is here: >> https://github.com/ianozsvald/EuroPython2011_HighPerformanceComputing/tree/master/mandelbrot/python >> >> shedskin2.py is available here: >> https://github.com/ianozsvald/EuroPython2011_HighPerformanceComputing/tree/master/mandelbrot/shedskin >> >> I haven't tested whether the warm-up periods for PyPy are significant, >> possibly they account for much of the difference between ShedSkin and >> PyPy? I want to revisit this but for the next few weeks I have to go >> back to other projects. > > Most come from the fact that you're using lists and not say > array.array (or numpy array), so the storage is not optimized. > ShedSkin doesn't allow you to store different types in a list. We'll > make it fast one day even if you use list, but indeed, using > array.array would make it much faster. > > Cheers, > fijal > -- Ian Ozsvald (A.I. researcher, screencaster) i...@ianozsvald.com http://IanOzsvald.com http://SocialTiesApp.com/ http://MorConsulting.com/ http://blog.AICookbook.com/ http://TheScreencastingHandbook.com http://FivePoundApp.com/ http://twitter.com/IanOzsvald _______________________________________________ pypy-dev mailing list pypy-dev@python.org http://mail.python.org/mailman/listinfo/pypy-dev
