[Python-Dev] Re: PEP 282 comments

[Jeremy Hylton]

>>>>> "KB" == Kevin Butler <kbutler@campuspipeline.com> writes:

  KB> [Jeremy]
  >> Why do you need **kwargs at all?

  KB> So we can postpone formatting the optional arguments into a
  KB> message until after we test if we're going to log the message or
  KB> not.

Aha!  I must have gone out of my way to miss this.  This is certainly
a good thing.  In the case of the ZEO server, we put all the trace and
debug level logging calls inside "if __debug__:"  We see a 20% speedup
on compute intensive benchmarks when running with -O.  So avoiding the
string formatting is a nice savings.

On the other hand, extended calls -- where the caller passes *args or
**args -- are a lot slower than regular calls.  It would be
interesting to benchmark both approaches.  I expect that no-formatting
is faster, but wouldn't bet too much on it.  Apps probably still
benefit from exploting if __debug__.

Jeremy