The No. 1 position was again claimed by the BlueGene/L System, a joint development of IBM and DOE’s National Nuclear Security Administration (NNSA) and installed at DOE’s Lawrence Livermore National Laboratory in Livermore, Calif. BlueGene/L also occupied the No. 1 position on the last three TOP500 lists. It has reached a Linpack benchmark performance of 280.6 TFlop/s (“teraflops” or trillions of calculations per second) and still remains the only system ever to exceed the level of 100 TFlop/s. This system is expected to remain the No. 1 Supercomputer in the world for the next few editions of the TOP500 list.