[Beowulf] IBM Sequoia

[Kilian CAVALOTTI]

On Wednesday 04 February 2009 14:23:01 John Hearns wrote:
> Yes, the Hpcwire article confirms 1.6Pbyte.
> http://www.hpcwire.com/features/Lawrence-Livermore-Prepares-for-20-Petaflop
>-Blue-GeneQ-38948594.html It also examines the core count:
> "However, since Sequoia will be composed of 98,304 compute nodes and
> contain a total of 1.6 million cores, one can surmise that a Blue
> Gene/Q node will contain 16 cores. Whether this is implemented as one
> 16-core chip or two 8-core chips (or even four quad-core chips)
> remains to be seen."

Seems right. 

According to 
http://www.cse.scitech.ac.uk/disco/mew17/talks/Keable_IBM_MEW17.pdf (slides 25 
and following) BG/Q will feature a "similar number of nodes", but with "many 
more cores". 

And according to 
http://www.theregister.co.uk/2008/07/11/ibm_power7_ncsa/, POWER7 chips will 
feature 8 cores (and 4 threads per core!). Pack two of thoses in a compute 
card, 32 compute cards per node card, and 32 node cards per rack, it gives 
1.52 million cores in 93 racks. Which marketing writes as 1.6 million, the 
count is right. :)

But even so, with a TDP of say 100W for the POWER7 chip, it's about 19MW of 
heat to cool down. Just for the CPUs... 

Liquid nitrogen anyone?

Cheers,
-- 
Kilian