Acceleration with long vector architectures: Implementation and evaluation of the FFT kernel on NEC SX-Aurora and RISC-V vector extension

Novel architectures leveraging long and variable vector lengths like the NEC SX-Aurora or the vector extension of RISCV are appearing as promising solutions on the supercomputing market. These architectures often require re-coding of scientific kernels. For example, traditional implementations of al...

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Detalles Bibliográficos
Autores: Vizcaíno Serrano, Pablo, Mantovani, Filippo|||0000-0003-3559-4825, Ferrer Ibañez, Roger, Labarta Mancho, Jesús José|||0000-0002-7489-4727
Tipo de recurso: artículo
Fecha de publicación:2022
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:2117/376024
Acceso en línea:https://hdl.handle.net/2117/376024
https://dx.doi.org/10.1002/cpe.7424
Access Level:acceso abierto
Palabra clave:Supercomputers
Vector processing (Computer science)
Fast Fourier transform
FFT
NEC SX-Aurora
RISC-V
SIMD
Vector acceleration
Supercomputadors
Tractament vectorial
Àrees temàtiques de la UPC::Informàtica::Arquitectura de computadors
Descripción
Sumario:Novel architectures leveraging long and variable vector lengths like the NEC SX-Aurora or the vector extension of RISCV are appearing as promising solutions on the supercomputing market. These architectures often require re-coding of scientific kernels. For example, traditional implementations of algorithms for computing the fast Fourier transform (FFT) cannot take full advantage of vector architectures. In this article, we present the implementation of FFT algorithms able to leverage these novel architectures. We evaluate these codes on NEC SX-Aurora , comparing them with the optimized NEC libraries; and in a prototype of a RISC-V core with a vector processing unit. We present the benefits and limitations of two approaches of RADIX-2 FFT vector implementations. We show that our approach makes better use of the vector unit of the NEC SX-Aurora , reaching higher or equal performance than the optimized NEC library. More generally, we prove the importance of maximizing the vector length usage of the algorithm, taking advantage of the FFT properties to reduce long-latency vector operations, and reordering the instructions according to the specific hardware features to boost the performance of FFT-like computational kernels.