Supercomputers/Systems/Ookami
USA · decommissioned · hpc
Ookami
Also known as Ookami A64FX testbed
Operated by Stony Brook University .
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
- -
- Rpeak
- -
- Rmax ÷ Rpeak
- -
- Cores
- -
- 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 | - HPE (formerly Cray) Apollo 80 | Hewlett Packard Enterprise | - | Reported | stonybrook.eduarxiv.org |
| CPU | Fujitsu A64FX CPUs Armv8.2-A SVE · 48C · 2.2 GHz · 7 nm 176 A64FX compute nodes (48 cores each), 2 for debugging | Fujitsu | 176 reported | Reported | stonybrook.edu |
| Interconnect | NVIDIA InfiniBand HDR Interconnect Fat tree or dragonfly+ · 200 Gb/s per port · About 0.6 microseconds HDR 200 Gbit/s InfiniBand full fat tree | NVIDIA | - | Reported | arxiv.org |
The read
Stony Brook's NSF-funded (OAC 1927880) HPE Apollo 80 testbed of 176 Fujitsu A64FX nodes (48 cores, 32 GB HBM, 512 GB SSD each, two for debugging), the same CPU as Fugaku, on an HDR InfiniBand full fat tree with about 0.8 PB of Lustre; an ACCESS resource from October 2022. The decommission date is the end-of-life Stony Brook announced ('end of 2025', with a data-migration-only period in January and February 2026); shutdown itself was not confirmed in the pages fetched. No HPL or TOP500 figure was found.
Timeline
- 2025-12 Decommissioned source
Change history
- 2026-10-02 Added Ookami, Stony Brook's NSF-funded A64FX testbed
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 |
|---|---|---|
| arxiv.org | names system only | · counts: 176 |
| stonybrook.edu | names system, part and count | Fujitsu A64FX · counts: 176 |
Checked 2026-10-09 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.