According to the June update of the TOP500 list, which tracks 500 of the world's most powerful supercomputers, China has taken the number one spot with its LineShine supercomputer. This system is capable of running 2.198 ExaFLOPS when measured on HPL, making it the world's first system to exceed 2 ExaFLOPS in dual-precision FP64 data processing for sustained workloads. It has a theoretical peak performance of 2.736 ExaFLOPS, meaning the system can sustain about 80% of its peak performance. This setup is powered by a massive network of traditional CPUs, with no GPUs or other accelerators contributing to the high FP64 figure. While traditional data centers have shifted toward 8-bit FP8 data formats for AI workloads, scientific HPC systems and supercomputers continue to use the traditional FP64 data. The Chinese LineShine is the first-ever system to sustain over 2 ExaFLOPS of compute capability, surpassing U.S.-based El Capitan, Aurora, and Frontier.

The LineShine comprises 13.79 million ARMv9 cores, spread across 20,480 nodes in a non-uniform memory access (NUMA) configuration. Each node contains two LX2 CPUs, with 304 cores and 32 GB of HBM memory. The CPU uses HBM for fast memory access, then offloads to system DDR memory, which has about 256 GB per CPU. The CPU is split across two dies, each divided into four NUMA domains. Each NUMA domain contains 38 cores running at 1.55 GHz and has 4 GB of HBM assigned to it. Four of these NUMA domains make up a die, and each die is assigned 128 GB of DDR memory. This is likely DDR5, but we haven't confirmed those details yet.

The system draws 42.2 MW of power and achieves an efficiency of 52.07 GigaFLOPS/Watt. It is the only Exascale system in the TOP500 list that uses CPU-only compute power. A similar design was employed by the Japanese Fugaku supercomputer, but that system managed only about half an ExaFLOP of sustained throughput. Finally, the TOP500 list has verified the performance claims of the LineShine supercomputer, marking the first time a Chinese HPC entry has reached the top of the TOP500 list, officially ranked and verified.