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DARPA Targets Computing's Achilles Heel: Power
coondoggie writes "The power required to increase computing performance, especially in embedded or sensor systems has become a serious constraint and is restricting the potential of future systems. Technologists from the Defense Advanced Research Projects Agency are looking for an ambitious answer to the problem and will next month detail a new program it expects will develop power technologies that could bolster system power output from today's 1 GFLOPS/watt to 75 GFLOPS/watt."
No, the problem is getting hold of raw materials for batteries. Mobile computing is on the rise and the west doesn't want to be too dependent on foreign mineral deposits. More efficient computers = smaller batteries = smaller amounts of lithium etc needed.
The problem is not just generating the power... it's delivering it and consuming it without breaking/melting. And that's what they're getting at here - getting more FLOPS per watt... not finding out how to push more watts into a system. A silly amount of the energy going into a supercomputer comes out as heat... and a silly amount of energy is then used to remove that heat. Hopefully, by significantly improving the energy efficiency of chips and systems, we can make them a lot more powerful without them needing a whole lot more power. And I haven't even mentioned the mobile/embedded side of the spectrum where its about battery life and comfortable operating temperatures... the same energy efficiency goals apply.
This is the sort of thing we over the pond are very interested in too. Like for example *cough* the Microelectronics Research Group that I'm a part of.
It occurred to me the other day that, while I have been programming and working with network monitoring tools and the like for a while, and I can get an email alert (or text message) whenever a piece of equipment goes down, the rest of the world doesn't have that sort of capability. A big chunk of of California Highway 1 could fall into the ocean, and people could fall off after it, and no one would notice until someone called it in. If my hard disk is on fire, I can get a message, but if the woods are on fire, you need to wait for someone to see the smoke.
Sensors and the like are pretty awesome to have.
The World Wide Web is dying. Soon, we shall have only the Internet.
In a sense. There is a widespread view that we will need 1 Exaflop supercomputers by roughly 2019 or 2020 for a whole range of applications including aircraft design, biochemistry to processing data from new instruments like the square kilometer array. On current trends, such a computer will need gigawatts of power (literally), which amongst other things would force it to be located right next to a large power station that wasn't needed for other purposes. This is felt to be a bit of a problem and this DARPA initiative is just one small part of the effort to tackle this and get the Exaflop machine down to 50MW or so, which is the most that can be routinely supplied by standard infrastructure.
Concidering energy does not come cheap there is a very good commercial reason to save on one of the larger costs in computing (or any other activity)
And even though the US hosts the worldleaders in denial of CO2 related climate change it is still an ever more important concideration for many people, even in the US.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
The amount of computation done per unit energy, isn't really the issue. Instead the problem is the amount of _USEFUL_ computation done per unit energy.
The majority of power in a modern system goes into moving data around, and other tasks which are not the actual desired computation. Examples of this are incrementing the program counter, figuring out instruction dependancies, and moving data between levels of caches. The actual computation of the data is tiny in comparison.
Why do we do this then? Most of the power goes to what is informally called the "Turing Tax" - the extra things required to allow a given processor to be general purpose - ie. to compute anything. A single purpose piece of hardware can only do one thing, but is vastly more efficient, because all the power used figuring out which bits of data need to go where can all be left out. Consider it like the difference between a road network that lets you go anywhere and a road with no junctions in a straight line between your house and your work. One is general purpose (you can go anywhere), the other is only good for one thing, but much quicker and more efficient.
To get nearer our goal, computers are getting components that are less flexible. Less flexibility means less Turing Tax. For example video encoder cores can do massive amounts of computation, yet they can only encode video - nothing else. For comparison, an HD video camera can record 1080p video in real time with only a couple of Watts. A PC (without hardware encoder) would take 15 mins or so to encode each minute of HD video, using far more power along the way.
The future of low power computing is to find clever ways of making special purpose hardware to do the most computationally heavy stuff such that the power hungry general purpose processors have less stuff left to do.
In a pinch you can extract lithium from sea water. That's basically what a lithium deposit is... an old sea that dried up and left the salts. Lithium isn't a big fraction of a battery's cost, weight or volume. Please everyone stop being silly. The cobalt that is often used in lithium batteries is far more expensive, rare and used in larger proportions. We just don't call them cobalt batteries so no one knows about that part.
And with GPU assist an Atom with a low-end GPU can happily play 1080P H.264.
Actually that depends on the bitrate of the encoding far more than whether it's "1080p" or not. I've seen plenty of "1080p H.264 video" that's got lousy quality the moment there's any action.
Not to mention the what profile of h264 was being used. High Profile requires much more computational power than Main. We're also assuming the video can be GPU accelerated. You can't just take any h264 video and get hardware acceleration, the video has to be encoded following certain rules about bitrate, b-frames, etc otherwise it will be all decoded in software.