Japan · operational · mixed

Genkai

Operated by RIIT, Kyushu University at Kyushu University Ito Campus .

Phase 1 seed dataset, compiled by hand. These rows were built from public operator, laboratory and vendor sources. A mechanical second-reader pass has since fetched every cited source: 1092 of 1153 systems have a readable citation that names them, and 40 are genuinely weakly sourced. Every claim carries its source and a confidence tier. Treat anything below verified as a lead, not a citation.

Measured performance

Rmax: 6.22 PFlop/s
Rpeak: 7.47 PFlop/s
Rmax ÷ Rpeak: 83.3%
Cores: 122,880
Power: 967.43 kW
Per watt: 6.4 GF/W

Figures are as last publicly reported for the configuration described below, not a live measurement. Where a system was upgraded in place, the post-upgrade configuration is shown and the earlier one appears in the timeline.

What this machine is made of

One row per supplier relationship. “Supplier at build” is the company that shipped the part at the time; where that company has since been acquired, the parent it rolls up to today is shown beside it. That distinction is what makes ticker-level aggregation possible across a thirty-year dataset.

Role	Part	Supplier at build	Quantity	Confidence	Source
Integrator	- Fujitsu PRIMERGY CX2550 M7 (Node Group A)	Fujitsu 6702TSE	-	Reported	top500.org
Accelerator	- NVIDIA H100: four per node on 38 Node Group B nodes plus eight per node on two Node Group C nodes	NVIDIA NVDANASDAQ	168 estimated	Reported	cc.kyushu-u.ac.jp
CPU	- Intel Xeon Platinum 8490H 60C 1.9GHz, 1,024 CPU-only nodes in Node Group A	Intel INTCNASDAQ	-	Reported	top500.org cc.kyushu-u.ac.jp
Interconnect	NVIDIA InfiniBand NDR (Quantum-2) Interconnect Fat tree or dragonfly+ · 400 Gb/s per port · Under 0.6 microseconds InfiniBand NDR200/NDR400 full-bisection fat tree	NVIDIA NVDANASDAQ	-	Reported	cc.kyushu-u.ac.jp top500.org

The read

Kyushu University's supercomputer on the Ito Campus, in service from October 2024 after test operation from July, with users migrating from the earlier ITO system. Node Group A is 1,024 CPU-only nodes with Intel Xeon Platinum 8490H (60-core) processors, Node Group B is 38 nodes with four NVIDIA H100 GPUs each, and Node Group C is two nodes with eight H100 each, all on InfiniBand NDR200/NDR with 55.2 PB of HDD and 737.28 TB of SSD storage. TOP500 lists only Node Group A: 122,880 cores, Rmax 6.22 and Rpeak 7.47 PFlop/s at 967.43 kW, 178th on its November 2024 debut and 238th in November 2025. Kyushu quotes 7.76 PFlop/s CPU and 5.63 PFlop/s GPU double-precision for the whole system, so the figures here are the CPU partition's. TOP500 is the only source for Rmax and core count, so the tier is reported.

Timeline

2024-10 First operational source
2025-11 List debut at #238 (November 2025) source

Public list appearances

Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.

#238: TOP500, November 2025 →

Site & facility

Kyushu University Ito Campus

Location: Fukuoka, Japan

cc.kyushu-u.ac.jp top500.org

Change history

2026-10-02 Genkai added, from TOP500 and Kyushu University

Source check

We fetched this system's own citations and recorded whether each page actually mentions it. This is a corroboration signal, not a fact check, and it is published so you can see how well the sourcing holds up rather than take it on trust.

Cited source	Result	Found on the page
top500.org	names system and part	NVIDIA InfiniBand NDR (Quantum-2)
cc.kyushu-u.ac.jp	names system and part	NVIDIA InfiniBand NDR (Quantum-2)

Checked 2026-10-09 by pnpm verify. Re-run it and the table changes with the web.