High-Q Club Launched

Following the first JUQUEEN Porting and Tuning workshop in February, a number of applications have since been scaled across the entire 28-rack BlueGene/Q machine at JSC. To encourage other developers to invest in tuning and scaling their codes and to promote the idea of exascale computing, JSC has established the High-Q Club, an exclusive set of codes capable of utilizing all of the 458,752 cores – and typically more than 1 million threads – of JUQUEEN.

Members so far include: waLBerla, a Lattice Boltzmann solver from the University of Erlangen-Nürnberg; Terra-Neo, a multigrid solver for geophysics applications, also from the Erlangen group; Gysela, a gyrokinetic code from CEA, France, for modelling fusion core plasmas; dynQCD, a Lattice QCD code developed at the University of Wuppertal and JSC; and PEPC, a tree algorithm developed at JSC for electrostatic and gravitational N-body problems. In the last example, PEPC was able to utilize a total of 458,752 MPI tasks and 1,668,196 parallel threads to compute long-range electrostatic forces between 65 billion particles – a new record for this class of N-body code.

To qualify for High-Q Club status, application developers should submit evidence of scalability across all available cores on JUQUEEN, preferably including multi-threading capability. High-Q Club membership updates including technical details of applications' performance and qualification rules are available at http://www.fz-juelich.de/ias/jsc/high-q-club.
(Contact: Dr. Dirk Brömmel, d.broemmel@fz-juelich.de)

from JSC News No. 213, 17 June 2013