FugakuNEXT is the codename for the follow-on flagship supercomputer for Japan after Fugaku. It is slated to be deployed in 2029 for operations in 2030, and RIKEN is the development lead for the system. Its high-level goals include:

  • 5x to 10x improvement in HPC application performance over Fugaku
  • more than 50 EFLOPS for AI training (100-200 EFLOPS peak)
  • 50x-100x application speedup when using AI surrogates

The system performance requirement for the RFP is:1

MetricCPUGPU
FP64 vector48 PF3,000 PF
FP16/BF16 matrix1,500 PF150,000 PF
FP8 matrix3,000 PF300,000 PF
Memory capacity10 PiB10 PiB
Memory bandwidth8 PB/s800 PB/s
In addition, they expect:

The storage subsystem will be two tiers:1

TierArchitectureImplementationBandwidthIOPSCapacity
FirstNear-node localSomething like CHFS, BeeONDWrite memory in less than 1 minuteOpen/close/stat file per process in under 1 second2x memory
SecondSharedLustre, DAOS20% of first tier10% of first tier30x memory

The project timeline is as follows:1

The details of the project were summarized on a digital poster at SC24:

Satoshi Matsuoka has been talking about their vision for FugakuNEXT since around 2022. The vision for its CPU is:2

Themes that may be relevant to a processor or node include:21

  • 3D stacking of memory and logic (as depicted above)
  • Silicon photonics
  • Large SRAMs, a la AMD 3D VCache
  • Specialized tensor core-like data paths for scientific motifs like stencils, convolution, FFTs
  • CGRA instead of or in addition to SIMD
  • Processing-in-memory (PIM)

The CGRA is called out as a “strong scaling accelerator” candidate, so perhaps the CPU socket will have tiles of general-purpose CPU cores as well as CGRA tiles.

Footnotes

  1. スパコンを使った 最先端の天気予報研究 (science.osti.gov) 2 3 4

  2. スパコンを使った 最先端の天気予報研究 (bnl.gov) 2