Lighter and faster simulations on domains with symmetries

A strategy to improve the performance and reduce the memory footprint of simulations on meshes with spatial reflection symmetries is presented in this work. By using an appropriate mirrored ordering of the unknowns, discrete partial differential operators are represented by matrices with a regular b...

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Detalles Bibliográficos
Autores: Alsalti Baldellou, Àdel|||0000-0002-5331-4236, Álvarez Farré, Xavier|||0000-0002-1684-7658, Colomer Rey, Guillem|||0000-0003-4592-0217, Gorobets, Andrei, Pérez Segarra, Carlos David|||0000-0003-1007-3142, Oliva Llena, Asensio|||0000-0002-2805-4794, Trias Miquel, Francesc Xavier|||0000-0002-5966-0703
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/407072
Acceso en línea:https://hdl.handle.net/2117/407072
https://dx.doi.org/10.1016/j.compfluid.2024.106247
Access Level:acceso abierto
Palabra clave:Computer simulation
Computational fluid dynamics
Symmetry (Mathematics)
Reflection symmetries
Arithmetic intensity
Memory footprint
SpMV
SpMM
MPI+OpenMP+OpenCL/CUDA
Simulació per ordinador
Dinàmica de fluids computacional
Simetria (Matemàtica)
Àrees temàtiques de la UPC::Informàtica::Aplicacions de la informàtica::Aplicacions informàtiques a la física i l‘enginyeria
Àrees temàtiques de la UPC::Enginyeria mecànica::Mecànica de fluids
Descripción
Sumario:A strategy to improve the performance and reduce the memory footprint of simulations on meshes with spatial reflection symmetries is presented in this work. By using an appropriate mirrored ordering of the unknowns, discrete partial differential operators are represented by matrices with a regular block structure that allows replacing the standard sparse matrix–vector product with a specialised version of the sparse matrix-matrix product, which has a significantly higher arithmetic intensity. Consequently, matrix multiplications are accelerated, whereas their memory footprint is reduced, making massive simulations more affordable. As an example of practical application, we consider the numerical simulation of turbulent incompressible flows using a low-dissipation discretisation on unstructured collocated grids. All the required matrices are classified into three sparsity patterns that correspond to the discrete Laplacian, gradient, and divergence operators. Therefore, the above-mentioned benefits of exploiting spatial reflection symmetries are tested for these three matrices on both CPU and GPU, showing up to 5.0x speed-ups and 8.0x memory savings. Finally, a roofline performance analysis of the symmetry-aware sparse matrix–vector product is presented.