JUQUEEN Extreme Scaling Workshop
In conjunction with this year's JUQUEEN Porting and Tuning Workshop, which is part of the PRACE Advanced Training Centres curriculum, JSC continued its series of Blue Gene Extreme Scaling Workshops from 5 to 6 February 2015. Seven application teams were invited to stay for two days and work on the scalability of their codes, with dedicated access to the entire JUQUEEN system for a period of 30 hours. Most of the teams' codes overlapped thematically with JSC Simulation Laboratories or were part of an ongoing collaboration with one of the SimLabs. The teams came from the fields of climate science (ICON from DKRZ, and MPAS-A from KIT and NCAR), engineering (FEMPAR from UPC, and ex_nl/FE2 from the University of Cologne and TU Freiberg), fluid dynamics (psOpen and SHOCK both from RWTH Aachen University), and neuroscience (CoreNeuron from the EPFL Blue Brain Project) and were supported by JSC SimLabs and cross-sectional teams, with technical support from IBM and JUQUEEN administrators. Within the first 24 hours of dedicated access to all 28 racks, all seven teams had adapted their codes and datasets to exploit the massive parallelism and restricted node memory for successful executions using all 458,752 cores. They also demonstrated excellent strong or weak scalability which qualified all but one team for the High-Q Club. A total of 370 'large' jobs were executed using 12 of the 15 million core hours of compute time allocated for the workshop.
Detailed results for each code, provided by the application teams themselves, and an analysis comparing them to the 16 existing High-Q Club codes can be found in the JSC technical report FZJ-JSC-IB-2015-01: https://juser.fz-juelich.de/record/188191/files/FZJ-2015-01645.pdf
(Contact: Dr. Brian Wylie, b.wylie@fz-juelich.de)
JSC News, 10 March 2015