What's Under the Hood? Air Force Scientists Build Supercomputer Using Game Consoles.
"My kids wanted to play the games bundled with the system," said Dr. Richard Linderman, AFRL Information Directorate chief scientist. "I wanted to see what the processor inside the PS3 could do. I already knew it had the potential for high-performance computer applications."
After researching the processor, Dr. Linderman and fellow scientists realized they had the backbone for a new take on supercomputer design. However, with a limited budget and cell processor servers costing thousands of dollars apiece, the scientists working out of the Rome Research Site in New York realized the reality of building such a supercomputer seemed unlikely.
That was until the scientists thought outside the box, or rather, off the shelf, and managed to build one of the world's most powerful computers for a fraction of the cost.
In what Dr. Linderman refers to as a $2 million side bet, the directorate spent about $300,000 on off-the-shelf Sony Playstation 3s and proved they could connect the consoles' cell processor into a computer cluster.
"With 336 consoles, we reached 53 TFLOPS [Tera Floating Point Operations per Second]," said Dr. Linderman. "With an additional $2 million in funding from the Department of Defense's High Performance Computing Modernization Program, we increased the cluster to 2,016 consoles and 500 TFLOPS in performance."
EYE IN THE SKY
The cluster, known as the Condor Cluster, includes servers with general purpose graphical processor units. It is intended for a persistent surveillance role using the synthetic aperture radar and algorithms developed for a sister project, the GOTCHA synthetic aperture radar. With the power of the PS3 cluster and aerial surveillance, scientists will be able to monitor a 25-km area in real time.
"By using the cell processors in the PS3s and the GPGPUs in unison, we've produced a system that does a very good job at handling this kind of information," said Mark Barnell, the project engineer for the cluster and AFRL high performance computing director. "We've developed the most powerful heterogeneous supercomputer in the world for a fraction of the cost of building it using individual chips and servers."
The Condor cluster looks more like a PS3 storage room than what some might imagine a supercomputer should look like. Thousands of consoles are stacked side-by-side on bread racks with homemade power management and mounting brackets. However, there is function and purpose in this construction.
"The PS3s arrive stacked on pallets," said Mr. Barnell. "We store them in one of the lab's warehouses and, after cataloging and testing each unit, we install them in racks of about 24. These modular racks can then be connected to the cluster as needed."
PUTTING IT IN PERSPECTIVE
A floating point operation is a single operation done by a computer. The PS3 cluster is capable of performing 500 trillion operations every second. That's about a third of the speed of the third fastest computer in the world, the IBM Roadrunner computer used by the Department of Energy.
According to Mr. Barnell, the Roadrunner cost more than $120 million dollars to build, a 60-fold increase in cost for three times the performance of the AFRL cluster. However, the savings aren't limited to the upfront cost of building the computer. Modern computers require huge amounts of energy to run. Fortunately for AFRL, Sony had already figured out how to make the consoles energy efficient.
"The PS3, which is designed to function in a living room, requires a very efficient power requirement," said Dr. Linderman. "They also have a sleep feature when they're not in use. This means that when they aren't in use they only use a fraction of the power."
The Condor cluster exceeded Dr. Linderman's expectations the day he brought that first PS3 home. However, only one version of the console can be used in the system, and Mr. Barnell bought every one he could find.
"The server runs on a Linux operating system that isn't available on the newer firmware of current systems," said Mr. Barnell. "We have to abide by the end-user license agreement like everyone else, so we're only able to use the systems as we get them."
If a Condor PS3 breaks it can't be sent in for repairs because it comes back with system updates that are unable to run Linux. After an update, it's useless in the Condor cluster.
"I have a few spares," he said. "But as they break, we'll end up removing consoles from the cluster."
The Condor cluster did accomplish what it was built to do. It's proven the abilities of a heterogeneous computer cluster and the feasibility of using off-the-shelf components as parts. As the Condor is eclipsed by more advanced technology, Mr. Barnell is looking to the next high-performance computer challenge; though he still has an appreciation for the PS3.
"If we had four times as many consoles, we could achieve roughly the processing power of the human brain," he said. "Imagine what we could do then."
STORY BY STAFF SGT. J. PAUL CROXON
PHOTOS BY MASTER SGT. JACK BRADEN
|Printer friendly Cite/link Email Feedback|
|Author:||Croxon, J. Paul|
|Date:||Nov 1, 2010|
|Previous Article:||Medal of honor.|
|Next Article:||New Horizons: Airmen Making Life Better in Panama.|