Supercomputers/Systems/CEA-HF
France · operational · hpc
CEA-HF
Also known as EXA1-HF
Operated by CEA .
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
- 23.24 PFlop/s
- Rpeak
- 31.76 PFlop/s
- Rmax ÷ Rpeak
- 73.2%
- Cores
- 810,240
- Power
- 4.96 MW
- Per watt
- 4.7 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 | - Bull/Eviden BullSequana XH2000 | Eviden | - | Verified | top500.orgcea.fr |
| CPU | AMD EPYC 7763 (Milan) CPUs x86-64 · 64C · 2.45 GHz · 7 nm · 280 W AMD EPYC 7763 64C 2.45GHz | AMD | - | Reported | top500.org |
| Interconnect | Eviden BXI v2 Interconnect Fat tree or dragonfly+ · 100 Gb/s per port Atos BXI V2 | Eviden | - | Verified | top500.orgcea.fr |
| Cooling | Direct liquid cooling, warm water Cooling Direct-to-chip cold plates, facility water loop · Removes 90+ percent of node heat to liquid Atos/Eviden Direct Liquid Cooling (DLC), water cooled | Eviden | - | Reported | cea.fr |
The read
The general-purpose CPU system of CEA's EXA1 program, developed by CEA's Military Applications Division (DAM) with Atos, now Eviden: a BullSequana XH2000 with AMD EPYC 7763 64C processors, BXI v2 interconnect and direct liquid cooling. TOP500 lists 810,240 cores, Rmax 23.24 PFlop/s, Rpeak 31.76 PFlop/s and 4,959 kW; CEA's launch announcement quotes 23.2 PFlop/s, 4.96 MW and 829,440 cores across 12,960 AMD processors, so the core counts differ and the TOP500 figure is kept. It debuted at 14th on the November 2021 TOP500, its best rank. The pages fetched give neither an installation site nor a workload, so the system is left unlocated and classed hpc. It is the CPU counterpart of the GH200-based CEA-HE recorded separately.
Timeline
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Change history
- 2026-10-02 Added CEA-HF, the CEA/DAM BullSequana EPYC system, 14th on the November 2021 TOP500
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 | AMD EPYC 7763 (Milan) |
| cea.fr | blocked our fetch | - |
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.