Dissertação de Mestrado

Performance Monitoring and Event-based Sampling for RISC-V

Tiago Alfredo Lopes Rocha 2023

Informações chave

Autores:

Tiago Alfredo Lopes Rocha (Tiago Alfredo Lopes Rocha)

Orientadores:

Nuno Filipe Simões Santos Moraes da Silva Neves (Nuno Filipe Simões Santos Moraes Neves), Pedro Filipe Zeferino Aidos Tomás (Pedro Filipe Zeferino Tomás)

Publicado em

04/12/2023

Resumo

Increased attention to RISC-V open Instruction Set Architecture (ISA), has fueled its move from embedded devices to the high-performance computing arena, with the proliferation of RISC-V-based accelerators. However, the absence of powerful performance monitoring tools often results in poorly optimized applications and, consequently, limited computing performance. While the RISC-V ISA already defines a Hardware Performace Monitor and offers support for the Linux perf_events subsystem, research and development on RISC-V-based devices have been more focused on architectures and compilers rather than tools to support monitoring performance. To overcome this limitation, the introduction of PAPI library support for RISC-V processors is proposed in this thesis, and a Precise Event Sampling system specification compatible with future PAPI integration is presented along with a minimal implementation proof-of-concept. The conducted testing and evaluation of the PAPI port were carried out on a SiFive Unmatched board, but the proposed changes, and the corresponding implementation, are easily portable to other systems. The proof of concept for RISC-V Precise Event Sampling was implemented on a CVA6 processor. It was found that, when compared to directly using perf_events, PAPI presents a large overhead; 83360µs in comparison with perf_events 100.24µs. Nevertheless, most of it (81200µs) is concentrated in the initialization of the library, which only occurs once per program execution.

Detalhes da publicação

Autores da comunidade :

Orientadores desta instituição:

Domínio Científico (FOS)

- Engenharia Eletrotécnica, Eletrónica e Informática

Idioma da publicação (código ISO)

- Inglês

Acesso à publicação:

Embargo levantado

Data do fim do embargo:

22/09/2024

Nome da instituição

Instituto Superior Técnico