Whilst RISC-V has grown phenomenally quickly in embedded computing, it is yet to gain significant traction in High Performance Computing (HPC). However, as we move further into the exascale era, the flexibility offered by RISC-V has the potential to be very beneficial in future supercomputers especially as the community places an increased emphasis on decarbonising its workloads. Sophon's SG2042 is the first mass produced, commodity available, high-core count RISC-V CPU designed for high performance workloads. First released in summer 2023, and at the time of writing now becoming widely available, a key question is whether this is a realistic proposition for HPC applications. In this paper we use NASA's NAS Parallel Benchmark (NPB) suite to characterise performance of the SG2042 against other CPUs implementing the RISC-V, x86-64, and AArch64 ISAs. We find that the SG2042 consistently outperforms all other RISC-V solutions, delivering between a 2.6 and 16.7 performance improvement at the single core level. When compared against the x86-64 and AArch64 CPUs, which are commonplace for high performance workloads, we find that the SG2042 performs comparatively well with computationally bound algorithms but decreases in relative performance when the algorithms are memory bandwidth or latency bound. Based on this work, we identify that performance of the SG2042's memory subsystem is the greatest bottleneck.

翻译：尽管RISC-V在嵌入式计算领域取得了惊人的快速发展，但在高性能计算（HPC）领域尚未获得显著的市场渗透。然而，随着我们进一步迈入百亿亿次计算时代，RISC-V所提供的灵活性有望在未来超级计算机中发挥重要作用，尤其是当业界日益重视计算负载的低碳化转型之际。算能的SG2042是首款大规模量产、商业化供应的高核数RISC-V处理器，专为高性能工作负载设计。该处理器于2023年夏季首次发布，截至本文撰写时已实现广泛供货，其核心问题在于它是否真正适用于HPC应用场景。本文采用美国国家航空航天局（NASA）的NAS并行基准测试套件，将SG2042与采用RISC-V、x86-64及AArch64指令集架构的其他处理器进行性能对比分析。研究发现SG2042在所有RISC-V解决方案中持续保持性能领先，在单核层面实现2.6至16.7倍的性能提升。与当前高性能工作负载领域主流的x86-64和AArch64处理器相比，SG2042在计算密集型算法中表现出相对竞争力，但在内存带宽或延迟敏感型算法中相对性能有所下降。基于本研究，我们确认SG2042内存子系统的性能是当前最主要的瓶颈所在。