Is RISC-V ready for HPC prime-time: Evaluating the 64-core Sophon SG2042 RISC-V CPU (2309.00381v2)

Published 1 Sep 2023 in cs.DC

Abstract: The Sophon SG2042 is the world's first commodity 64-core RISC-V CPU for high performance workloads and an important question is whether the SG2042 has the potential to encourage the HPC community to embrace RISC-V. In this paper we undertaking a performance exploration of the SG2042 against existing RISC-V hardware and high performance x86 CPUs in use by modern supercomputers. Leveraging the RAJAPerf benchmarking suite, we discover that on average, the SG2042 delivers, per core, between five and ten times the performance compared to the nearest widely available RISC-V hardware. We found that, on average, the x86 high performance CPUs under test outperform the SG2042 by between four and eight times for multi-threaded workloads, although some individual kernels do perform faster on the SG2042. The result of this work is a performance study that not only contrasts this new RISC-V CPU against existing technologies, but furthermore shares performance best practice.

References (16)

Authors (4)

Nick Brown (67 papers)
Maurice Jamieson (12 papers)
Joseph Lee (14 papers)
Paul Wang (4 papers)

Citations (4)

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Summary

Evaluating the Sophon SG2042 RISC-V CPU: An Insight into Its HPC Potential

The paper "Is RISC-V ready for HPC prime-time: Evaluating the 64-core Sophon SG2042 RISC-V CPU" critically assesses the performance of the Sophon SG2042 CPU, providing a detailed analysis of its applicability and competitiveness in the field of High-Performance Computing (HPC). This research elucidates the potential shift toward RISC-V architecture within HPC environments by comparing this novel CPU against both existing RISC-V hardware and established x86 CPUs prevalent in current supercomputing systems.

Key Highlights and Findings

The Sophon SG2042 represents a significant advancement by introducing a 64-core RISC-V processor aimed explicitly at high-performance workloads. The paper employs the RAJAPerf benchmarking suite to explore the SG2042's performance capabilities against its RISC-V contemporaries, like the SiFive VisionFive V1 and V2, equipped with U74 cores. The findings illustrate a striking performance improvement, where the SG2042's XuanTie C920 core delivers, on average, between five and ten times better performance in single-precision calculations compared to the U74 core. For double-precision tasks, the C920 shows three to six times better performance than its predecessor.

The research further explores the threading and vectorisation attributes of the SG2042. It is evident that optimal thread placement, taking into account NUMA regions and core clusters, is crucial for harnessing its full potential. The performance benefits of vectorisation are more pronounced with single-precision tasks, highlighting RVV (RISC-V Vector extension) advantages, albeit limited by current compiler capabilities and vector length specifics.

In comparing with x86 CPUs, the SG2042 demonstrates commendable multi-threaded performance, albeit overshadowed by robust competition from chips like the AMD Rome EPYC 7742, Intel Broadwell, and Ice Lake processors. Although the SG2042 lags behind in certain benchmarks, particularly those leveraging AVX and AVX-512 instruction sets, it shows competitiveness against older architectures such as Intel's Sandybridge.

Implications and Future Perspectives

The performance insight presented in this paper indicates the Sophon SG2042 as a critical milestone in RISC-V's journey towards HPC adoption. While the SG2042 does not yet rival top-tier x86 processors in terms of raw performance, it provides a base for future RISC-V developments that could, with enhancements in vectorisation support and architectural refinements, bring RISC-V into closer competitiveness with existing HPC stalwarts.

Future efforts could focus on the development of compiler support for RVV v1.0, enabling a more seamless transition and optimum utilisation of available vectorisation capabilities. Further exploration on distributed memory and MPI performance could also shed light on the SG2042's capabilities in large-scale HPC applications.

This paper serves as a foundational paper for the HPC community to assess serious RISC-V hardware candidates, indicating that although RISC-V has not reached parity with x86 equivalents, the gap narrows continuously. Continued architectural enhancements, coupled with strategic software developments, might well position RISC-V as a formidable competitor in the ever-evolving HPC landscape.