[tlug] "Mine is bigger than yours"

["SL Baur" <steve@example.com>]

(Seen on /. http://tech.slashdot.org/comments.pl?sid=973601&cid=25129479)

Wow.  And you gotta love the easy-to-use comment.
"It's just Linux."  I suppose the real question is, is XEmacs
redisplay fast enough?

-sb

[Begin quoted comment]
I write massively parallel scientific code that runs on these
supercomputers for a living... and this is what I've been preaching
all along.

The thing about RoadRunner and others (such as Red Storm at Sandia) is
that they are special pieces of hardware that run highly specialized
operating systems. I can say from experience that these are an
_enormous_ pain in the ass to code for... and reaching anything near
the theoretical computing limit on these machines with real world
engineering applications is essentially impossible... not too mention
all of the extra time it costs you in just getting your application to
compile on the machine and debug it...

My "day-to-day" supercomputer is a 2048 processor machine made up of
generic Intel cores all running a slightly modified version of Suse
Linux. This is a great machine for development _and_ for execution. My
users have no trouble using my software and the machine... because
it's just Linux.

When looking at a supercomputer I always think in terms of utility...
not in terms of Flops. It's for this reason that I think the guys down
at the Texas Advanced Computing Center got it right when they built
Ranger ( http://www.tacc.utexas.edu/resources/hpcsystems/#constellation
[utexas.edu] ). It's about a half a petaflop... but guess what? It
runs Linux! And is actually made up of a bunch of Opteron cores... the
machine itself is also a huge, awesome looking beast (I've been inside
it... the 2 huge Infiniband switches are really something to see). I
haven't used it myself (yet), but I have friends working at TACC and
everyone really likes the machine a lot. It definitely strikes that
chord between ultra-powerful and ultra-useful.

Friedmud