[Radiance-general] multiprocessor systems, Radiance, and you

[Rob Guglielmetti]

Howdy folks-

After spending the last couple of months getting up to speed with 
Radiance (the workshop in Freibourg was really, really, good at showing 
me how much I had to learn, how behind the curve I was [am]), and 
performing hunderds of rtrace jobs, and compiling a cohesive analytical 
report on the data, our client has responded:

They want more.

You all know how it is, once you show someone what is possible with 
Radiance, they start thinking "what would it look like if we did this, 
or this, or this, or this, etc, etc....".  So we intend to show them 
some of these options.

While I'm thrilled to be doing more with Radiance, I'm now Desperately 
Seeking Cycles, CPU horsepower that is.  After Jack's fifteen minute 
rendering claim at the workshop -- Yes Jack, that's what you said, we 
all heard you ;-) -- for a single dual Athlon box, I'm thinking this is 
what I want to do.  I don't need NFS lock headaches right now, I have 
enough problems.  So I'm looking to build one very fast box, and I'm 
hoping to make it a dualie, and skip the LAN based render farm for now.

(several paragraphs later he gets to the questions...)  My questions are 
for those of you on the list with MP linux experience.  I guess I'm hazy 
on the way the two processors are utilized.  Do you tend to run one job 
on one CPU and a second one on the other, or do you use rpiece to work 
one job across both, as if the the CPUs are two different hosts?  Or is 
there some OS and/or Radiance compile tweak that you do to simply make 
both CPUs act as one, obviating the need for rpiece? Seems like you 
still need rpiece so the ambient cache is managed properly. As far as 
CPU, do I *have* to use the Athlon MP, or can I run two XPs?  Anyone 
have hardware recommendations?  I like Abit motherboards, but they don't 
seem to offer a dual socket variant.  What about OS?  I had great 
success with RHL 8.0 on an old Dell -- it installed and compiled 
Radiance without a single hiccup.  Anyone using it on a dual box?  Any 
compile changes to either the OS or Radiance?

Any info, urls or advice would be greatly appreciated.

----

      Rob Guglielmetti

e. rpg@rumblestrip.org
w. www.rumblestrip.org