Jaime Vives Piqueres wrote:
> Warp wrote:
> 
> 
>>  I am wondering if it's a good idea to keep such slow version of povray
>>for linux in www.povray.org if even gcc2 can do such good job at
>>optimizing.
>>  By the way, how is it possible that the official version is so slow? Was
>>it compiled with no optimizations at all?-o
> 
> 
>  Only -O2... but I think what make the great difference is using specific 
> -mcpu and -march. Perhaps for the official distribution -O3 can be used, 
> but not much more can be done, I think, except encouraging to compile the 
> sources for your rendering palataform, perhaps with recommended flags. It's 
> not that difficult at all: I myself have done it and I've no knowledge 
> about c, c++, compilers and optimization. 
> 

Yes, the cpu targeting helps some. But it turns out to help a lot just 
to get the -O2 optimization settings in both CFLAGS and CXXFLAGS. The 
default compiliation only put the -g -O2 flags in CFLAGS. I ran 
benchmark.pov against a build with only the -O2 optimization flag in 
both CFLAGS and CXXFLAGS and here's the resulting times:

default options (only in CFLAGS) = 55m 40s (3340s)
-O2 optimized (in both directives) = 29m 1s (1741s)

So maybe just getting a build based on the intended optimizations would 
be a good thing to provide on the POV-Ray web site.

-Roz

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