[Python-3000] Performance Notes

[Nicholas Bastin]

I've been doing some profiling of 3.0 vs. 2.6 release builds on
Windows XP for the purpose of hopefully closing the performance gap.
This data is very preliminary, but I thought I'd throw it out here in
case someone else also wanted to look into this.  Also, possibly
useful for comparing against profiling data on other platforms.  The
table below just lists functions and speed differentials in 3.0 vs.
2.6, ordered by the functions in which we spend the most total time.

NOTE:  This data is time sampling, not call graph.  Added time could
come from either more calls, or longer calls.

+  11.5% PyEval_EvalFrameEx
+  40.2% lookdict (replacing lookdict_string)
+312.9% PyDict_GetItem
-   13.2% call_function
+  19.4% fast_function

Other notes:
* PyLong_FitsInLong consumes about 2% of total pystone runtime.
* unicode_compare consumes the exact same time in 3.0 that
string_richcompare consumed in 2.6.  Either these functions share a
similar CPU profile, or their call counts vary dramatically.

Top 5 functions in Python 2.6:

* PyEval_EvalFrameEx (48.66%)
* lookdict_string (5.76%)
* call_function (4.80%)
* frame_dealloc (2.80%)
* fast_function (2.48%)

Top 5 functions in Python 3.0:

* PyEval_EvalFrameEx (44.37%)
* lookdict (6.66%)
* PyDict_GetItem (4.63%)
* unicode_hash (3.51%)
* call_function (3.38%)

--
Nick