RSON: An inter/intra-chip silicon photonic network for rack-scale computing systems

The increasing demand for more computational power from scientific computing, big data processing, and machine learning is pushing the development of HPC (high-performance computing) systems. As the basic HPC building blocks, modularized server racks with a large number of multicore nodes are facing performance and energy efficiency challenges. This paper proposes RSON, an optical network for rack-scale computing systems. RSON connects processor cores, caches, local memories, and remote memories through a novel inter/intra-chip silicon photonic network architecture. We develop a low-latency scalable channel partition and low-power dynamic path priority control scheme for RSON. Experimental results show that RSON can help rack-scale computing systems achieve up to 6.8X higher performance under the same energy consumption than state-of-the-art systems under the latest APEX (application performance at extreme scale) benchmarks.