[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>.
give-me-two-weeks-of-uninterrupted-time-with-a-hw-simulator-and-you'll-
get-a-real-answer-ly y'rs - tim