Publications

Bertagna, Luca B.; Guba, Oksana G.; Bradley, Andrew M.; Salinger, Andrew G.; Taylor, Mark A.; Foucar, James G.

Abstract not provided.

International Conference for High Performance Computing, Networking, Storage and Analysis, SC

Bertagna, Luca B.; Guba, Oksana G.; Taylor, Mark A.; Foucar, James G.; Larkin, Jeff; Bradley, Andrew M.; Rajamanickam, Sivasankaran R.; Salinger, Andrew G.

We present an effort to port the nonhydrostatic atmosphere dynamical core of the Energy Exascale Earth System Model (E3SM) to efficiently run on a variety of architectures, including conventional CPU, many-core CPU, and GPU. We specifically target cloud-resolving resolutions of 3 km and 1 km. To express on-node parallelism we use the C++ library Kokkos, which allows us to achieve a performance portable code in a largely architecture-independent way. Our C++ implementation is at least as fast as the original Fortran implementation on IBM Power9 and Intel Knights Landing processors, proving that the code refactor did not compromise the efficiency on CPU architectures. On the other hand, when using the GPUs, our implementation is able to achieve 0.97 Simulated Years Per Day, running on the full Summit supercomputer. To the best of our knowledge, this is the most achieved to date by any global atmosphere dynamical core running at such resolutions.

Bertagna, Luca B.; Guba, Oksana G.; Foucar, James G.; Taylor, Mark A.; Bradley, Andrew M.; Salinger, Andrew G.

Abstract not provided.

Bertagna, Luca B.; Guba, Oksana G.; Taylor, Mark A.; Foucar, James G.; Larkin, Jeff L.; Bradley, Andrew M.; Rajamanickam, Sivasankaran R.; Salinger, Andrew G.

Abstract not provided.

Hillman, Benjamin H.; Caldwell, Peter C.; Salinger, Andrew G.; Bertagna, Luca B.; Beydoun, Hassan B.; Peter, Bogenschutz.P.; Bradley, Andrew M.; Donahue, Aaron D.; Eldred, Christopher; Foucar, James G.; Golaz, Chris G.; Guba, Oksana G.; Jacob, Robert J.; Johnson, Jeff J.; Keen, Noel K.; Krishna, Jayesh K.; Lin, Wuyin L.; Liu, Weiran L.; Pressel, Kyle P.; Singh, Balwinder S.; Steyer, Andrew S.; Taylor, Mark A.; Terai, Chris T.; Ullrich, Paul A.; Wu, Danqing W.; Yuan, Xingqui Y.

Abstract not provided.

Bertagna, Luca B.; Jakeman, John D.; Perego, Mauro P.; Kalashnikova, Irina; Watkins, Jerry E.; Salinger, Andrew G.; Asay-Davis, Xylar A.; Hoffman, Matthew J.; Price, Stephen F.; Zhang, Tong Z.; Stadler, Georg S.

Abstract not provided.

Geoscientific Model Development

Bertagna, Luca B.; Deakin, Michael; Guba, Oksana G.; Sunderland, Daniel S.; Bradley, Andrew M.; Kalashnikova, Irina; Taylor, Mark A.; Salinger, Andrew G.

We present an architecture-portable and performant implementation of the atmospheric dynamical core (High-Order Methods Modeling Environment, HOMME) of the Energy Exascale Earth System Model (E3SM). The original Fortran implementation is highly performant and scalable on conventional architectures using the Message Passing Interface (MPI) and Open MultiProcessor (OpenMP) programming models. We rewrite the model in C++ and use the Kokkos library to express on-node parallelism in a largely architecture-independent implementation. Kokkos provides an abstraction of a compute node or device, layout-polymorphic multidimensional arrays, and parallel execution constructs. The new implementation achieves the same or better performance on conventional multicore computers and is portable to GPUs. We present performance data for the original and new implementations on multiple platforms, on up to 5400 compute nodes, and study several aspects of the single-and multi-node performance characteristics of the new implementation on conventional CPU (e.g., Intel Xeon), many core CPU (e.g., Intel Xeon Phi Knights Landing), and Nvidia V100 GPU.

Geoscientific Model Development

Lipscomb, William H.; Price, Stephen F.; Hoffman, Matthew J.; Leguy, Gunter R.; Bennett, Andrew R.; Bradley, Sarah L.; Evans, Katherine J.; Fyke, Jeremy G.; Kennedy, Joseph H.; Perego, Mauro P.; Ranken, Douglas M.; Sacks, William J.; Salinger, Andrew G.; Vargo, Lauren J.; Worley, Patrick H.

We describe and evaluate version 2.1 of the Community Ice Sheet Model (CISM). CISM is a parallel, 3-D thermomechanical model, written mainly in Fortran, that solves equations for the momentum balance and the thickness and temperature evolution of ice sheets. CISM's velocity solver incorporates a hierarchy of Stokes flow approximations, including shallow-shelf, depth-integrated higher order, and 3-D higher order. CISM also includes a suite of test cases, links to third-party solver libraries, and parameterizations of physical processes such as basal sliding, iceberg calving, and sub-ice-shelf melting. The model has been verified for standard test problems, including the Ice Sheet Model Intercomparison Project for Higher-Order Models (ISMIP-HOM) experiments, and has participated in the initMIP-Greenland initialization experiment. In multimillennial simulations with modern climate forcing on a 4 km grid, CISM reaches a steady state that is broadly consistent with observed flow patterns of the Greenland ice sheet. CISM has been integrated into version 2.0 of the Community Earth System Model, where it is being used for Greenland simulations under past, present, and future climates. The code is open-source with extensive documentation and remains under active development.

Bertagna, Luca B.; Deakin, Michael D.; Guba, Oksana G.; Sunderland, Daniel S.; Bradley, Andrew M.; Kalashnikova, Irina; Taylor, Mark A.; Salinger, Andrew G.

Abstract not provided.

Peterson, Kara J.; Perego, Mauro P.; Frederick, Jennifer M.; Wheeler, Lauren B.; Bosler, Peter A.; Ruffing, Anne R.; Davis, Ryan W.; Whitmore, Leanne S.; Poorey, Kunal N.; Williams, Kelly P.; Roesler, Erika L.; Bryan, Paul F.; Salinger, Andrew G.; Hardesty, Jasper O.; Tidwell, Vincent C.; Singh, Anup K.

Abstract not provided.

Baczewski, Andrew D.; Gao, Xujiao G.; Jacobson, Noah T.; Nielsen, Erik N.; Salinger, Andrew G.; Muller, Richard P.; Gamble, John K.

Abstract not provided.

Bertagna, Luca B.; Deakin, Michael D.; Guba, Oksana G.; Sunderland, Daniel S.; Bradley, Andrew M.; Kalashnikova, Irina; Taylor, Mark A.; Salinger, Andrew G.

Abstract not provided.

Perego, Mauro P.; Bertagna, Luca B.; Hoffman, Matthew J.; Jakeman, John D.; Price, Stephen F.; Salinger, Andrew G.; Stadler, Georg S.; Kalashnikova, Irina; Watkins, Jerry E.

Abstract not provided.

Salinger, Andrew G.; Bertagna, Luca B.; Bradley, Andrew M.; Deakin, Michael D.; Guba, Oksana G.; Sunderland, Daniel S.; Kalashnikova, Irina

Abstract not provided.

Tuminaro, Raymond S.; Perego, Mauro P.; Kalashnikova, Irina; Salinger, Andrew G.; Price, Steven P.

Abstract not provided.

Kalashnikova, Irina; Jakeman, John D.; Eldred, Michael S.; Perego, Mauro P.; Price, Stephen F.; Salinger, Andrew G.

Abstract not provided.

Tuminaro, Raymond S.; Perego, Mauro P.; Kalashnikova, Irina; Salinger, Andrew G.; Price, Stephen F.

Abstract not provided.

Perego, Mauro P.; Salinger, Andrew G.; Price, Stephen F.

Abstract not provided.

Barone, Alessandro B.; Perego, Mauro P.; Salinger, Andrew G.; Hoffman, Matthew J.; Stadler, Georg S.; Zhu, Hongyu Z.

Abstract not provided.

Kalashnikova, Irina; Salinger, Andrew G.; Perego, Mauro P.; Tuminaro, Raymond S.; Jakeman, John D.; Eldred, Michael S.; Watkins, Jerry E.; Price, Stephen F.; Demeshko, Irina P.

Abstract not provided.

Barone, Alessandro B.; Perego, Mauro P.; Salinger, Andrew G.

Abstract not provided.

Tuminaro, Raymond S.; Cyr, Eric C.; Shadid, John N.; Noble, David R.; Berger-Vergiat, Luc B.; Hu, Jonathan J.; Prokopenko, Andrey P.; Siefert, Christopher S.; Wiesner, Tobias A.; Perego, Mauro P.; Salinger, Andrew G.; Kalashnikova, Irina; Price, Stephen F.

Abstract not provided.

Bosler, Peter A.; Bova, S.W.; Demeshko, Irina P.; Fike, Jeffrey A.; Guba, Oksana G.; Overfelt, James R.; Roesler, Erika L.; Salinger, Andrew G.; Smith, Thomas M.; Kalashnikova, Irina; Watkins, Jerry E.

The Next Generation Global Atmosphere Model LDRD project developed a suite of atmosphere models: a shallow water model, an x - z hydrostatic model, and a 3D hydrostatic model, by using Albany, a finite element code. Albany provides access to a large suite of leading-edge Sandia high- performance computing technologies enabled by Trilinos, Dakota, and Sierra. The next-generation capabilities most relevant to a global atmosphere model are performance portability and embedded uncertainty quantification (UQ). Performance portability is the capability for a single code base to run efficiently on diverse set of advanced computing architectures, such as multi-core threading or GPUs. Embedded UQ refers to simulation algorithms that have been modified to aid in the quantifying of uncertainties. In our case, this means running multiple samples for an ensemble concurrently, and reaping certain performance benefits. We demonstrate the effectiveness of these approaches here as a prelude to introducing them into ACME.

Kalashnikova, Irina; Salinger, Andrew G.; Perego, Mauro P.; Tuminaro, Raymond S.; Price, Stephen F.; Watkins, Jerry E.; Hansen, Glen H.

Abstract not provided.

Tuminaro, Raymond S.; Perego, Mauro P.; Kalashnikova, Irina; Salinger, Andrew G.

Abstract not provided.