[Python-Dev] Re: Python 2.1 slower than 2.0
Jeremy Hylton
jeremy@alum.mit.edu
Mon, 29 Jan 2001 12:27:08 -0500 (EST)
>>>>> "ESR" == Eric S Raymond <esr@thyrsus.com> writes:
ESR> Jeremy Hylton <jeremy@alum.mit.edu>:
>> The strange thing is that I notice a difference between -O2 and
>> -O3 with 2.1a1, but in the opposite direction. On pystone,
>> python -O2 runs consistently faster than -O3; the difference is
>> .05 sec on my machine.
ESR> Bizarre. Make me wonder if we have a C compiler problem.
Depends on your defintion of "compiler problem" <wink>. If you mean,
it compiles our code so it runs slower, then, yes, we've got one :-).
One of the differences between -O2 and -O3, according to the man page,
is that -O3 will perform optimizations that involve a space-speed
tradeoff. It also include -finline-functions. I can imagine that
some of these optimizations hurt memory performance enough to make a
difference.
not-really-understanding-but-not-really-expecting-too-ly y'rs,
Jeremy