In this paper, we analyze the performance and energy consumption of an Arm-based high-performance computing (HPC) system developed within the European project Mont-Blanc 3. This system, called Dibona, has been integrated by ATOS/Bull, and it is powered by the latest Marvell’s CPU, ThunderX2. This CPU is the same one that powers the Astra supercomputer, the first Arm-based supercomputer entering the Top500 in November 2018. We study from micro-benchmarks up to large production codes. We include an interdisciplinary evaluation of three scientific applications (a finite-element fluid dynamics code, a smoothed particle hydrodynamics code, and a lattice Boltzmann code) and the Graph 500 benchmark, focusing on parallel and energy efficiency as well as studying their scalability up to thousands of Armv8 cores. For comparison, we run the same tests on state-of-the-art x86 nodes included in Dibona and the Tier-0 supercomputer MareNostrum4. Our experiments show that the ThunderX2 has a 25% lower performance on average, mainly due to its small vector unit yet somewhat compensated by its 30% wider links between the CPU and the main memory. We found that the software ecosystem of the Armv8 architecture is comparable to the one available for Intel. Our results also show that ThunderX2 delivers similar or better energy-to-solution and scalability, proving that Arm-based chips are legitimate contenders in the market of next-generation HPC systems.

在本文中，我们分析了在欧洲勃朗峰3号项目中开发的基于Arm的高性能计算（HPC）系统的性能和能耗。该系统名为Dibona，已由ATOS / Bull集成，并且由最新的Marvell CPU ThunderX2供电。该CPU与为Astra超级计算机提供动力的CPU相同，Astra超级计算机是第一台基于Arm的超级计算机，于2018年11月进入Top500。我们研究的范围从微基准测试到大型生产代码。我们包括对三个科学应用程序的跨学科评估（有限元流体动力学代码，平滑粒子流体动力学代码和晶格Boltzmann代码）和Graph 500基准测试，着重于并行和能效以及研究其可扩展性直至数千个Armv8内核。为了比较，我们在Dibona和Tier-0超级计算机MareNostrum4中包含的最新x86节点上进行了相同的测试。我们的实验表明，ThunderX2的性能平均降低了25％，这主要是由于其较小的向量单元，而CPU和主内存之间的链接宽度却增加了30％，这在一定程度上弥补了这种不足。我们发现Armv8架构的软件生态系统与Intel可用的软件生态系统相当。我们的结果还表明，ThunderX2提供了相似或更好的能源解决方案和可扩展性，证明基于Arm的芯片是下一代HPC系统市场上的合法竞争者。主要是由于其较小的向量单位，但CPU和主存储器之间的链接宽度增加了30％，从而在一定程度上弥补了这种不足。我们发现Armv8架构的软件生态系统与Intel可用的软件生态系统相当。我们的结果还表明，ThunderX2提供了相似或更好的能源解决方案和可扩展性，证明基于Arm的芯片是下一代HPC系统市场上的合法竞争者。主要是由于其较小的向量单位，但CPU和主存储器之间的链接宽度增加了30％，从而在一定程度上弥补了这种不足。我们发现Armv8架构的软件生态系统与Intel可用的软件生态系统相当。我们的结果还表明，ThunderX2提供了相似或更好的能源解决方案和可扩展性，证明基于Arm的芯片是下一代HPC系统市场上的合法竞争者。