[Python-Dev] Python 2.3 release schedule

Tim Peters tim.one@comcast.net
Sun, 26 May 2002 15:27:29 -0400

[Guido, to Oren Tirosh]
> ...
> Also note that your patch slows down fast access (by 3%)!  How can it?
> Adding more code to the interpreter's inner loop changes the cache
> behavior, etc.  Tim Peters can tell you more about this.

Not unless someone pays me to <wink>.  Here's a cute one:  I changed the
"break" at the end of LOAD_GLOBAL to "continue".  It didn't change the speed
of global-lookup tests at all, but did give a small boost to fastlocal
lookups.  On several occasions we've seen evidence that ceval is supremely
sensitive to I-cache accidents, although Marc-Andre is a lot better at
provoking them than I am <wink -- but IIRC he once got a 15% slowdown by
adding an unreachable(!) printf to ceval>.

    get-a-real-answer-ly y'rs  - tim