For some reason the list seems to occasionally drop my messages... Francesc Alted wrote: > A Friday 22 May 2009 13:52:46 Andrew Friedley escrigué: >> I'm the student doing the project. I have a blog here, which contains >> some initial performance numbers for a couple test ufuncs I did: >> >> http://numcorepy.blogspot.com
>> Another alternative we've talked about, and I (more and more likely) may >> look into is composing multiple operations together into a single ufunc. >> Again the main idea being that memory accesses can be reduced/eliminated. > > IMHO, composing multiple operations together is the most promising venue for > leveraging current multicore systems. Agreed -- our concern when considering for the project was to keep the scope reasonable so I can complete it in the GSoC timeframe. If I have time I'll definitely be looking into this over the summer; if not later. > Another interesting approach is to implement costly operations (from the > point > of view of CPU resources), namely, transcendental functions like sin, cos or > tan, but also others like sqrt or pow) in a parallel way. If besides, you > can > combine this with vectorized versions of them (by using the well spread SSE2 > instruction set, see [1] for an example), then you would be able to achieve > really good results for sure (at least Intel did with its VML library ;) > > [1] http://gruntthepeon.free.fr/ssemath/ I've seen that page before. Using another source [1] I came up with a quick/dirty cos ufunc. Performance is crazy good compared to NumPy (100x); see the latest post on my blog for a little more info. I'll look at the source myself when I get time again, but is NumPy using a Python-based cos function, a C implementation, or something else? As I wrote in my blog, the performance gain is almost too good to believe. [1] http://www.devmaster.net/forums/showthread.php?t=5784 Andrew _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
