On 5/4/06, Josiah Carlson <[EMAIL PROTECTED]> wrote: > > "Guido van Rossum" <[EMAIL PROTECTED]> wrote: > > Can you please post the benchmarking code? > > No problem.
OK, so I have the advantage of a time machine... Or at least the p3yk (sic) branch. I created a perhaps more reasonable benchmark; you can see it in SVN here: http://svn.python.org/view/sandbox/trunk/sio/bench_cat.py?rev=45918&view=log Run with the latest Python 3.0, this shows clearly that the += idiom is slower than the join idiom, although not by that much. It also shows that the straightforward mutable bytes implementation in 3.0 consistently performs better than the string implementation -- probably due to being able to resize the buffer without moving the object. Or maybe I missed something? The benchmark concatenates 100,000 strings with a size uniformly chosen from range(N) where N ("size" below) is varied from 10 to 1000 for different test runs. That means the final string varies between 0.5 MB to 50 MB. Each result represents the best of 3 runs where each run executes the above concatenation loop 10 times. Here are the results (on a 1.67 GHz PowerBook): ------ size = 10 ------ bytes+= 0.401 bytes.join 0.221 str+= 0.552 str.join 0.279 ------ size = 20 ------ bytes+= 0.419 bytes.join 0.236 str+= 0.565 str.join 0.305 ------ size = 50 ------ bytes+= 0.518 bytes.join 0.340 str+= 0.713 str.join 0.405 ------ size = 100 ------ bytes+= 0.654 bytes.join 0.454 str+= 0.894 str.join 0.580 ------ size = 200 ------ bytes+= 0.878 bytes.join 0.642 str+= 1.179 str.join 0.823 ------ size = 500 ------ bytes+= 1.678 bytes.join 1.462 str+= 2.466 str.join 1.631 ------ size = 1000 ------ bytes+= 3.051 bytes.join 2.762 str+= 4.220 str.join 2.822 Gotta run, -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
