[Python-Dev] PyBench DictCreation (was Re: Performance compares)

[Jeremy Hylton]

>>>>> "TP" == Tim Peters <tim@digicool.com> writes:

  TP> I've got no interest in trying to restore the old behavior.  A
  TP> compromise may be to boost the minimum size of a non-empty dict
  TP> from 4 to 8.  As is, the only non-empty dicts that can get away
  TP> with using the current minimum size of 4 have no more than 2
  TP> elements.  The question is whether such tiny non-empty dicts are
  TP> common enough to make everyone else pay for "an extra" resize.

I also did a profile run on CreateInstances, which has a difference of
+55.54% on my machine.  It's basically the same story.  The instance
dictionary is getting resized more often with Python 2.1+ than it did
with Python 1.5.2.  I wouldn't be surprised if several more tests are
showing a slowdown with the same cause.

So boosting the minimum size sounds like a good thing.

Jeremy