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[ba-ohs-talk] Cringely on building a super computer

http://www.pbs.org/cringely/pulpit/pulpit20011227.html    (01)

 From the article:
" What's so clever about KLAT2 is the way the 64 separate PCs are linked 
together. This is the real bottleneck in building a high performance 
computer at low cost. Processors are cheap, memory is cheap, disk storage 
is cheap, but networking -- at least really fast networking -- is still 
expensive. To build a network capable of keeping up with those 64 Athlons, 
the obvious choice would have been to use gigabit Ethernet adapter cards. 
But gigabit Ethernet cards are expensive, and at the time would have cost 
more than the PCs in which they were installed. There had to be a cheaper 
way of connecting all those PCs together.    (02)

So Dietz came up with a whole new network topology that allows cheaper, 
slower network cards to perform as well or better than gigabit Ethernet. 
The solution was to put more cheap Ethernet cards in each PC, and then use 
"channel bonding" to make them all look like a single faster card. Dietz 
put four 100 megabit-per-second fast Ethernet cards in each PC. Each card 
has only one tenth the speed of a gigabit card, but not even gigabit 
Ethernet cards actually carry a billion bits per second. With channel 
bonding, it turns out that even using three cheap network cards per PC 
allows greater throughput than a single gigabit card. And fast Ethernet 
(10base-100) costs about three percent of gigabit Ethernet on a per-card 
basis, so using four cards per PC still saves 88 percent."    (03)

He talks about KLAT2
The Kentucky Linux Athlon Testbed
http://aggregate.org/KLAT2/    (04)

Cringely says this about KLAT2
" Building a supercomputer these days is pretty much a matter of throwing a 
lot of processors and memory into a big box or boxes, then finding some 
cheap clustering OS (usually Linux) to make it all work together. My role 
model in this venture is KLAT2, the Kentucky Linux Athlon Testbed 2, which 
in a recent ranking came up as the 200th most powerful supercomputer on the 
planet. I love the idea of a supercomputer from Kentucky, but I love even 
more the clever design of KLAT2, which is a cluster of 64 PCs each running 
a 700-MHz Athlon processor for a total of more than 64 gigaflops of 
number-crunching power. Built by University of Kentucky graduate students 
led by professor Hank Dietz, KLAT2 cost only $41,000, which is cheap for a 
supercomputer. "    (05)