The 39th edition of the Top500 list of the world's leading supercomputers has been revealed at the 2012 International Supercomputing Conference (ISC) in Hamburg, Germany. Sequoia, the IBM BlueGene/Q system installed at the Department of Energy’s Lawrence Livermore National Laboratory, has claimed the top spot – the first time since November 2009 that a United States supercomputer has done so. In addition to achieving 16.32 petaflops on the Linpack benchmark using 1,572,864 cores, Sequoia is one of the most energy efficient systems on the list.
Having claimed the leading position on the past two Top500 lists, Fujitsu's K Computer, installed at the RIKEN Advanced Institute for Computational Science (AICS) in Kobe, Japan, is now the number two system. It achieves 10.51 Pflops on the Linpack benchmark using 705,024 SPARC64 processing cores. Appearing for the first time on the list, third place goes to a US supercomputer located at the Argonne National Laboratory in Illinois. Named Mira, it is an IBM BlueGene/Q system with 8.15 petaflops on the Linpack benchmark using 786,432 cores.
The fourth position on the list goes to SuperMUC, an IBM iDataplex system installed at Leibniz Rechenzentrum in Germany, and Europe's leading supercomputer. The fifth and sixth spots are held by China's Tianhe-1A at the National Supercomputing Center in Tianjin and the upgraded Jaguar at Oak Ridge National Laboratory in Tennessee, US, respectively. FERMI, an IBM BlueGene/Q system installed at CINECA, comes in at number seven and represents Italy's debut in the Top 10, while the German JuQUEEN BlueGene/Q system at Forschungszentrum Juelich is eighth. Completing the Top 10 are a Bull supercomputer in France at number nine and Nebulae at the National Supercomputing Centre in Shenzhen, China in tenth position. It is worth noting that four of the Top 10 supercomputers are IBM BlueGene/Q systems.
The combined performance of the supercomputers on the previous list, released in November 2011, was 74.2 petaflops. Representing a significant increase since that time, the combined performance of this latest list is 123.4 petaflops. In total, 20 of the systems on this list have reached 1 petaflop or more and the 500th machine recorded a performance of 60.8 teraflops, which seven months ago was enough to place at number 332.
Intel processors are present in 74.4 per cent of the Top500 supercomputers – a total of 372 systems – down from 76.8 per cent (384 systems) on the previous list. The AMD Opteron line is used in 63 systems, the same number appearing in the last list, while the deployment of IBM Power processors has increased from 49 to 58 systems. Also rising is the number of systems using accelerators or co-processors. That figure stands at 58; 53 of which use Nvidia chips, two utilise Cell processors, two feature ATI Radeon and one system has Intel MIC technology.
