Rob Hoopman wrote:
> Those are the obvious ones and the ones I used already, my gcc is at 
> 2.95.3 is gcc 3+ used for the pov builds and could this result in a 
> significant speed gain?

gcc 3.1.1 did show a pretty good speed boost over gcc 2.96 (those are
the versions I tested). For instance, rendering benchmark.pov produced
the following times using the same optimization settings:

gcc 2.96:  28m 1s
gcc 3.1.1: 25m 14s

The prebuilt binary from 8/7/02 took 34m 10s (the earlier prebuilt binary
was MUCH slower).

> I'm not talking about a small increase, for illlustration a simple scene 
> ( FWIW: 4 panes of glass on a checkered floor using photons )
> 
> linux precompiled binary:
>     2 secs parse 55 secs trace
> native build:   
>     2 secs parse 201 secs trace
> 
> Something is _really_ strange here, this can't be only optimisation flags?
> 
> System Athlon TB 1Ghz, 512Mb CAS2.5 DDR SDRAM

You need to place the optimization flags in 2 places; at least that worked
for me. What I did was run the ./configure then edited the src/Makefile
and changed the CXXFLAGS and CFLAGS to the following:

CXXFLAGS = -g -O3 -s -mcpu=athlon -march=athlon -finline-functions 
-ffast-math \
-fomit-frame-pointer -Wall -funroll-loops -fexpensive-optimizations \
-malign-double -foptimize-sibling-calls -minline-all-stringops 
$(NOMULTICHAR)

CFLAGS = -g -O3 -s -mcpu=athlon -march=athlon -finline-functions 
-ffast-math \
-fomit-frame-pointer -Wall -funroll-loops -fexpensive-optimizations \
-malign-double -foptimize-sibling-calls -minline-all-stringops

You'll notice that they're almost identical except for the NOMULTICHAR part.

Hope this helps!

-Roz

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