[Beowulf] SiCortex experience anyone?

Lawrence Stewart larry.stewart at sicortex.com
Tue May 27 17:48:45 EDT 2008

I guess I am the token SiCortex person who posts here sometimes.   
There are probably other
lurkers as well.  Hopefully this is generic enough to not trigger a  
allergic response from the moderator...

The philosophical idea was something like noticing that HPC codes tend  
miss in the cache, with a "flops per miss" figure of merit.

So we tried to build a system with relatively less CPU but just as  
much memory
and very good communications.

As a consequence, we tend to do very well on communications intensive  
and relatively less well on codes that smell like DGEMM or which have an
unusually large amount of integer stuff.

As a general matter, your code will be limited by something (memory,  
comm, cpu,
I/O are the usual suspects), so a balanced system is one is which  
breaks at once.

We're probably unbalanced towards comms, whereas a commodity cluster is
(usually) unbalanced towards CPU.

Porting is pretty easy, in the sense that "configure" and "make" tend  
to just work,
but it isn't unusual to have to tune to get the best performance.   
We've worked
pretty hard to make the performance tools play well together.

Is it a beowulf?  The software philosophy is about the same, but the  
hardware isn't
really commodity, except the DIMMs.

Regarding scalability of the systems, they range from 72 to 5832  
cores, and are mostly
assembled from the same boards with different backplanes.  We think we  
know how to
cluster systems as well, should anyone turn up with a suitable  
suitcase of cash.


Beowulf mailing list, Beowulf at beowulf.org
To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf

This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.

More information about the Beowulf mailing list