English

Dissecting RISC-V Performance: Practical PMU Profiling and Hardware-Agnostic Roofline Analysis on Emerging Platforms

Performance 2025-07-31 v1

Abstract

As RISC-V architectures proliferate across embedded and high-performance domains, developers face persistent challenges in performance optimization due to fragmented tooling, immature hardware features, and platform-specific defects. This paper delivers a pragmatic methodology for extracting actionable performance insights on RISC-V systems, even under constrained or unreliable hardware conditions. We present a workaround to circumvent hardware bugs in one of the popular RISC-V implementations, enabling robust event sampling. For memory-compute bottleneck analysis, we introduce compiler-driven Roofline tooling that operates without hardware PMU dependencies, leveraging LLVM-based instrumentation to derive operational intensity and throughput metrics directly from application IR. Our open source toolchain automates these workarounds, unifying PMU data correction and compiler-guided Roofline construction into a single workflow.

Keywords

Cite

@article{arxiv.2507.22451,
  title  = {Dissecting RISC-V Performance: Practical PMU Profiling and Hardware-Agnostic Roofline Analysis on Emerging Platforms},
  author = {Alexander Batashev},
  journal= {arXiv preprint arXiv:2507.22451},
  year   = {2025}
}
R2 v1 2026-07-01T04:25:30.270Z