Supercomputers/Systems/Oakforest-PACS
Japan · decommissioned · hpc
Oakforest-PACS
Operated by JCAHPC at JCAHPC (Miyabi) .
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
- 13.55 PFlop/s
- Rpeak
- 24.91 PFlop/s
- Rmax ÷ Rpeak
- 54.4%
- Cores
- 556,104
- Power
- 2.72 MW
- Per watt
- 5.0 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 CX1640 M1 | Fujitsu | - | Verified | jcahpc.jptop500.org |
| Interconnect | Omni-Path Architecture Interconnect Fat tree · 100 Gb/s per port · About 1 microsecond Intel Omni-Path 100 Gbps full-bisection fat tree | Intel | - | Reported | cc.u-tokyo.ac.jp |
The read
The JCAHPC Fujitsu PRIMERGY system of 8,208 Xeon Phi 7250 nodes on Omni-Path, sixth on the November 2016 TOP500. The consortium's pages give October 2016 to March 2022 as its operating life; the two pages come from the consortium and its member university, so they are one source in effect. The Kashiwa campus is named on the consortium's slides but the city is not, so no coordinates are recorded. TOP500 is the only source for Rmax, Rpeak and core count, so the tier is reported.
Timeline
- 2016-10 First operational source
- 2016-11 List debut at #6 (November 2016) source
- 2022-03 Decommissioned source
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Site & facility
Change history
- 2026-09-20 Added with a rank pointer on the edition where it ranked highest
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 |
|---|---|---|
| jcahpc.jp | could not be fetched | - |
| top500.org | names system and part | Omni-Path Architecture |
Checked 2026-10-09 by pnpm verify. Re-run it and the table changes with the web.