Análise do Impacto de Runtimes Task-Based no Desempenho de Algoritmos de Álgebra Linear Densa

  • Matheus Augusto Tregnago UFRGS
  • Philippe O. A. Navaux UFRGS
  • Lucas Mello Schnorr UFRGS

Resumo


Runtimes de escalonamento de tarefas dependentes como StarPU e PaRSEC abstraem a complexidade de plataformas heterogêneas, mas adotam estratégias diferentes de escalonamento e gerenciamento de dados. Este trabalho compara o desempenho dos dois runtimes nas fatorações de Cholesky e LU sem pivotamento da biblioteca Chameleon, mantendo fixa a biblioteca de álgebra linear para isolar o efeito do runtime. Este estudo exigiu estender a interface Dynamic Task Discovery (DTD) do PaRSEC e os codelets do Chameleon com suporte a GPU. Os experimentos mostram que o StarPU é superior ou equivalente na maior parte dos casos. O parsec:gd só obtém vantagem na máquina com RTX 4070 (455 GFLOPS em FP64, aproximadamente metade da capacidade da CPU). Na máquina com RTX 4090 (1.290 GFLOPS, quase o dobro da CPU), o StarPU vence em toda a faixa avaliada, com cerca de 30% de vantagem mesmo no tamanho de bloco ótimo de cada runtime.

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Publicado
03/11/2026
TREGNAGO, Matheus Augusto; NAVAUX, Philippe O. A.; SCHNORR, Lucas Mello. Análise do Impacto de Runtimes Task-Based no Desempenho de Algoritmos de Álgebra Linear Densa. In: SIMPÓSIO EM SISTEMAS COMPUTACIONAIS DE ALTO DESEMPENHO (SSCAD), 27. , 2026, Natal/RN. Anais [...]. Porto Alegre: Sociedade Brasileira de Computação, 2026 . p. 99-111. DOI: https://doi.org/10.5753/sscad.2026.34369.