Supercomputers/Systems/T2K Kyodai
Japan · operational · hpc
T2K Kyodai
Also known as T2K Open Supercomputer/Kyodai; Fujitsu HX600 cluster
Operated by Kyoto University ACCMS .
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: 1263 of 1345 systems have a readable citation that names them, and 56 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
- 50.51 TFlop/s
- Rpeak
- 61.24 TFlop/s
- Rmax ÷ Rpeak
- 82.5%
- Cores
- 6,656
- Power
- -
- Per watt
- - 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 HX600 cluster of 416 nodes | Fujitsu | - | Reported | info.archives.global.fujitsutop500.org |
| CPU | - AMD quad-core Opteron 2.3 GHz, four per node, 416 nodes | AMD | - | Reported | info.archives.global.fujitsutop500.org |
| Interconnect | Mellanox InfiniBand DDR Interconnect Fat tree · 20 Gb/s per 4x port · About 2 microseconds InfiniBand DDR | Mellanox NVDANASDAQ
rolls up to NVIDIA | - | Reported | top500.org |
| Storage | - Fujitsu ETERNUS2000 model 200 disk arrays, 32 units, 800 TB | Fujitsu | - | Reported | info.archives.global.fujitsu |
The read
Kyoto University's member of the T2K alliance, built by Fujitsu to the shared T2K Open Supercomputer specification. Fujitsu's 2008 press release describes a main cluster of 416 PRIMERGY HX600 nodes, each with four quad-core AMD Opterons, 61.2 TFlop/s peak, InfiniBand, and 800 TB of disk on 32 ETERNUS2000 arrays. 416 nodes of 16 cores give the 6,656 cores TOP500 records, with 50.51 TFlop/s Rmax and 61.24 TFlop/s Rpeak (https://www.top500.org/system/175546/, 35th in June 2008, last listed June 2011). Trade press says the three T2K machines entered operation in June 2008 (https://hothardware.com/news/t2k-open-supercomputer-now-in-operation). Rmax rests on TOP500 alone, so the tier is reported. No site is recorded because the machine room is not named.
Timeline
- 2008-02 Announced source
- 2008-06 List debut at #35 (June 2008) source
- 2008-06 First operational source
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Change history
- 2026-10-09 Added T2K Kyodai
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 |
|---|---|---|
| info.archives.global.fujitsu | does not name this system | Mellanox InfiniBand DDR |
| top500.org | names system and part | Mellanox InfiniBand DDR |
Checked 2026-10-13 by pnpm verify. Re-run it and the table changes with the web.
Further reading
Operating a supercomputer
Acceptance testing, why "installed" and "in production" are six months apart, and the machine lifecycle.
Inside a node
Latency-optimised versus throughput-optimised processors, NUMA, and the end of the host-to-device copy.
The interconnect
Topologies, why latency and tail behaviour matter more than bandwidth, and how the fabric market consolidated.