Things we think the Python community will like.
- Frame optimizations: once a function is called it retains the allocated frame for use in future calls, avoiding allocation and initialization overhead. Frame size has also been slightly reduced.
PyStone is over 10% higher on RichardJones' test machine, compared to Python 2.4 (from 20242 to 22935). PyBench reports an overall slowdown, attributed to a 150% slowdown in a piece of code that wasn't changed. Sigh.
Made Gzip readline 30-40% faster (BobIppolito)
Speed up Unicode operations (AndrewDalke, FredrikLundh). Most notable, repeat is much faster, and most search operations (find, index, count, in) are a LOT faster (20x for the related stringbench tests). Also, rsplit is now as fast as split, and splitlines is nearly as fast as a plain split("\n"). Current stringbench results:
str(ms) uni(ms) % comment
-----------------------------------------------------
2271.31 3608.32 62.9 TOTAL 2.5a2
2261.85 1187.84 190.4 TOTAL tuesday
2227.48 1002.61 222.2 TOTAL wednesday- (yes, the Unicode string type is now more than twice as fast on this set of tests, and over 3.5 times faster than when we started. ymmv.)
Patch 1335972 was a combination bugfix+speedup for string->int conversion. These are the speedups measured on my Windows box for decimal strings of various lengths. Note that the difference between 9 and 10 is the difference between short and long Python ints on a 32-bit box. The patch doesn't actually do anything to speed conversion to long directly; the speedup in those cases is solely due to detecting "unsigned long" overflow more quickly:
length speedup
------ -------
1 12.4%
2 15.7%
3 20.6%
4 28.1%
5 33.2%
6 37.5%
7 41.9%
8 46.3%
9 51.2%
10 19.5%
11 19.9%
12 23.9%
13 23.7%
14 23.3%
15 24.9%
16 25.3%
17 28.3%
18 27.9%
19 35.7%The struct module has been rewritten to pre-compile struct descriptors (similar to the RE module). This gives a 20% speedup, on average, for the test suite [BobIppolito]. Taking advantage of new ability to "compile" a struct pattern (similar to compiling regexps) can be much faster still.