On Fri, 14 Nov 2003, Warp wrote:
>
>  If you are using Sun's CC compiler, just use "-fast". If you are using
>gcc, use "-O3 -ffast-math" (according to my experiments, no other
>optimization flags have any effect whatsoever; apparently they haven't
>developed the Sparc version of gcc too much).

If you are using the Sun One Studio 8 Compiler Collection then I assure you
that a simple -fast will not get you what you want.

>  CC gives about 5% faster binaries than gcc (but also larger).

Actually, depending on the scene file and the size of the output image you
will find that the binary produced by gcc will not work very well past a size
of about 10240x7680 pixels.  The 64-bit build of povray for the UltraSparc
works just fine at these sizes provided that you have the gigs of RAM needed.
I expect that the 64-bit build for Solaris 10 on the Opteron will be quite
fast.  Testing has begun on the Solaris 10 build 46 with dual Opteron servers
and I expect to be using a quad Opteron with Solaris this month.  I still use
PovRay for a lot of my benchmarking and number crunching and all I can tell
you is that they are really really fast.  The Linux kernel, on Red Hat 9 and
the same hardware, run well in 32-bit mode but can not address RAM past about
4Gb unless you tweak the kernel.  The 2.4.22 kernel ( see kernel.org ) will
allow the RAM addressing with a custom build but one needs to build a
monolithic kernel to get real speed.  Still, the Solaris 10 servers are faster
in head to head comparison.  Probably due to the mature kernel in Solaris.

[dclarke@appro dclarke]$ uname -a
Linux appro 2.4.22 #2 Sun Oct 19 00:58:28 EDT 2003 i686 i686 i386 GNU/Linux
[dclarke@appro dclarke]$ lsmod --version
lsmod version 2.4.25
[dclarke@appro dclarke]$ lsmod
Module                  Size  Used by    Not tainted


In any case, you can find well tuned builds of PovRay at www.blastwave.org

Dennis

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