No. 1 system in June 2012

For the first time since November 2009, a United States supercomputer sat atop the TOP500 list in June 2012. Named Sequoia, the IBM BlueGene/Q system installed at the Department of Energy’s Lawrence Livermore National Laboratory achieved 16.32 petaflop/s performance running the Linpack benchmark using 1,572,864 cores. Sequoia was the first system to be built using more than one million cores.

Sequoia is primarily water cooled and consists of 96 racks; 98,304 compute nodes; 1.6 million cores; and 1.6 petabytes of memory. Though orders of magnitude more powerful than such predecessor systems as ASC Purple and Blue Gene/L, Sequoia
is roughly 90 times more power efficient than Purple and about eight times more than BG/L relative to the peak speeds of these systems.

Sequoia will enable simulations that explore phenomena at a level of detail never before possible. Sequoia is dedicated to NNSA's Advanced Simulation and Computing (ASC) program for stewardship of the nation's nuclear weapons stockpile, a joint effort from LLNL, Los Alamos National Laboratory and Sandia National Laboratories.