It's official, IBM's Roadrunner supercomputer is the fastest – and most energy-efficient – of them all. The publication yesterday of the TOP500 list of the world's most powerful supercomputers confirms its position, and also points to the increasing dominance of Intel processors in the supercomputing field. 

The Roadrunner system, built by IBM for the US Department of Energy’s Los Alamos National Laboratory, performance of 1,026 petaflops, the first computer to break the petaflop barrier.
The 31st edition of the TOP500 list was released at the International Supercomputing Conference in Dresden, Germany.
“Over the past few months, there were a number of rumors going around about whether Roadrunner would be ready in time to make the list, as well as whether other high-profile systems would submit performance numbers,” says Erich Strohmaier, a computer scientist at Lawrence Berkeley National Laboratory and a founding editor of the TOP500 list. “So, as the reports came in during recent weeks, it’s been both exciting and challenging to compile this edition.”
The Roadrunner system displaces the reigning IBM BlueGene/L system at DOE’s Lawrence Livermore National Laboratory. Blue Gene/L, with a performance of 478.2 teraflops (trillions of floating point operations per second) is now ranked second after holding the top position since November 2004.
Rounding out the top five positions, all of which are in the US, are the new IBM BlueGene/P (450.3 teraflops) at DOE’s Argonne National Laboratory, the new Sun SunBlade x6420 “Ranger” system (326 teraflops) at the Texas Advanced Computing Center at the University of Texas, and the upgraded Cray XT4 “Jaguar” (205 teraflops) at DOE’s Oak Ridge National Laboratory.
Among all systems, Intel continues to power an increasing number, with Intel processors now found in 75% of the TOP500 supercomputers, up from 70,8% of the 30th list released last November.
Other highlights from the latest list include:
* Quad-core processor based systems have taken over the TOP500 quite rapidly – already 283 systems are using them; 203 systems are using dual-core processors; only 11 systems still use single core processors; and three systems use IBMs advanced Sony PlayStation 3 processor with nine cores.
* The top industrial customer, at number 10, is the French oil company: Total Exploration Production;
* IBM held on to its lead in systems with 210 systems (42%) over Hewlett Packard with 183 systems (36,6%). IBM had 232 systems (46,4%) six months ago, compared to HP with 166 systems (33,2%).
* IBM remains the clear leader in the TOP500 list in performance with 48% of installed total performance (up from 45%), compared to HP with 22,4% (down from 23,9%). In the system category Dell, SGI and Cray follow with 5,4%, 4,4% and 3,2% respectively.
* The last system on the list would have been listed at position 200 in the previous TOP500 just six months ago. This is the largest turnover rate in the 16-year history of the TOP500 project.
For the first time, the TOP500 list also provides energy efficiency calculations for many of the computing systems and will continue tracking them in consistent manner.
Most energy efficient supercomputers are based on IBM QS22 Cell processor blades (up to 488 Mflops/Watt) and IBM BlueGene/P systems (up to 376 Mflops/Watt).
Intel Harpertown quad-core blades are catching up fast, with the IBM BladeCenter HS21with low-power processors (up to 265 Mflops/Watt), the SGI Altix ICE 8200EX Xeon quad-core nodes, (up to 240 Mflops/Watt) and the Hewlett-Packard Cluster Platform 3000 BL2x220 with double density blades (up to 227 Mflops/Watt).
The number 6 system is the top system outside the US, installed in Germany at the Forschungszentrum Juelich (FZJ). It is an IBM BlueGene/P system and was measured at 180 Tflops.
The number 7 system is installed at a new center, the New Mexico Computing Applications Centre  in Rio Rancho. It is built by SGI and based on the Altix ICE 8200 model. It was measured at 133.2 Tflops.
For the second time, India placed a system in the top10. The Computational Research Laboratories, a wholly-owned subsidiary of Tata Sons, installed a Hewlett-Packard Cluster Platform 3000 BL460c system. They integrated this system with their own innovative routing technology and achieved a performance of 132.8 Tflops which was sufficient for number 8.
The No. 9 system is a new BlueGene/P system installed at the Institut du Développement et des Ressources en Informatique Scientifique (IDRIS) in France, which was measured at 112.5 Tflops.
The last new system in the Top 10 is also an SGI Altix ICE 8200 system. It is the biggest system installed at an industrial customer, Total Exploration Production. It was ranked based on a Linpack performance of 106.1 Tflops.
The US. is clearly the leading consumer of HPC systems with 257 of the 500 systems. The European share (184 systems, up from 149) is still rising and is again larger then the Asian share (48, down from 58 systems).
Dominant countries in Asia are Japan with 22 systems (up from 20), China with 12 systems (up from 10), India with six systems (down from nine) and Taiwan with three (down from 11).
In Europe, UK remains the number with 53 systems (48 six months ago). Germany improved but is still in the number 2 spot with 46 systems (31 six months ago).
The TOP500 list is compiled by Hans Meuer of the University of Mannheim, Germany; Erich Strohmaier and Horst Simon of NERSC/Lawrence Berkeley National Laboratory; and Jack Dongarra of the University of Tennessee, Knoxville.