I Feel Like a MHz Editor In an EHz World

After putting up with MHz (10⁶) for so long, I'm just getting used to GHz (10⁹). Which is why I find it numbing that the Institute for Advanced Architectures has set its sights on EHz (10¹⁸) scale computing.

That's 1 million trillion calculations per second, but who's counting. Another way to put this in perspective is that an exaflop is a thousand times faster than a petaflop, a petaflop is a thousand times faster than a teraflop. And a teraflop is a lot faster than the 1.7 MHz TRS-80 Model I that I once had. A whole lot faster. Take my word for it.

Of course, the Institute for Advanced Architectures, a joint project of the Sandia and Oak Ridge national labs, isn't quite there yet. It will take a few years; after all, they just started.

So what will an EHz computer look like? Think parallel--and in a big way. An EHz-scale computer will likely have tens of thousands of cores at its beck-and-call.

So what are the technological challenges? One big challenge is what's called the "mismatch between data movement and processing speeds." Sandia computer architect Doug Doerfler explains: "In an exascale computer, data might be tens of thousands of processors away from the processor that wants it. But until that processor gets its data, it has nothing useful to do. One key to scalability is to make sure all processors have something to work on at all times." Then there's also the power problem. The electricity needed to power an EHz computer is tens of megawatts--and today a megawatt can cost as much as a million dollars a year.

So if you've been holding back on buying that new laptop with a 2-GHz Centrino Duo processor on the off-chance that an EHz laptop might be right around the corner...

-- Jonathan Erickson
jerickson@ddj.com

Posted by Jon Erickson at 09:41 AM  Permalink