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From: Chuck Swiger <cswiger@mac.com>
To: Ivan Voras <ivoras@freebsd.org>
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Date: Fri, 8 Feb 2008 14:31:45 -0800
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On Feb 8, 2008, at 12:43 PM, Ivan Voras wrote:
>> Historically, the Python optimizer wasn't capable of doing much,  
>> true, but the more recent versions of the optimizer can actually do  
>> some peephole optimizations like algorithmic simplification and  
>> constant folding:
>> http://docs.python.org/whatsnew/other-lang.html#SECTION0001320000000000000000
>
> A quick test with the built-in pystone mini-benchmark (taken out of  
> the standard library so the optimization can be varied) yields [*]:
>
> python without -O : 5802.36
> python with -O : 5781.39

That's ~ 0.4% difference, or low enough to be lost in the noise, agreed.

I suspect that if the Python optimizer becomes smart enough to do dead- 
code elimination and code motion of invariants outside of loops that  
one would see a more significant difference.  At the present, it's  
only smart enough to optimize pretty dumb cases that most humans would  
already deal with...

-- 
-Chuck