Here’s my two bits from the story:

Brock Tice is one of those scientists. As vp of operations at the Baltimore, Maryland-based CardioSolv, he works to model, yes, the heart – simulating its mechanical and electrical activity. And though he can run some simulations on Amazon’s cloud – or on individual local machines – more complex models require HPC. “We’re [sic] tried on Amazon and it just doesn’t scale,” he tells The Reg. “We can run on single EC2 instances, but if we need to scale up to a dog or human heart, it’s just impossible.

“The connections between Amazon’s machines are Gigabit Ethernet and they’re shared. If you fire up 10 machines and you want to run them like a cluster, some might be in the same rack, and others might be halfway across the data center, five or six switches away.”

You can find the full story here.