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 and most search operations (find, index, count, in) are now a lot faster. 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
-----------------------------------------------------
2374.13 3786.27 62.7    TOTAL 2.5a2
2347.33 1335.65 175.7   TOTAL trunk

• 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). On average, this leads to a 20% speedup [BobIppolito].