JUWELS Cluster

Operated by Forschungszentrum Julich at Julich Supercomputing Centre .

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: 6.18 PFlop/s
Rpeak: 9.89 PFlop/s
Rmax ÷ Rpeak: 62.5%
Cores: 114,480
Power: 1.36 MW
Per watt: 4.5 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	- Atos BullSequana X1000	Eviden ATOEPA rolls up to Atos	-	Reported	fz-juelich.de top500.org
Accelerator	NVIDIA Tesla V100 Accelerators CUDA (Volta GV100) · 5,120C · 1.53 GHz · 12 nm · 300 W 56 accelerated nodes with four NVIDIA V100 16GB	NVIDIA NVDANASDAQ	224 estimated	Reported	apps.fz-juelich.de
Interconnect	Mellanox InfiniBand EDR Interconnect Fat tree · 100 Gb/s per 4x port · About 0.9 microseconds InfiniBand EDR fat tree with HDR top-level switches	NVIDIA NVDANASDAQ	-	Reported	apps.fz-juelich.de

The read

Julich's Eviden BullSequana X1000 general-purpose module, which TOP500 lists as JUWELS Module 1, 23rd on the June 2018 TOP500. JSC counts 122,768 cores against TOP500's 114,480 and quotes a larger peak that includes later additions, so TOP500's figures are used and the conflict is logged. JSC's system page and its journal paper are the same organization, so they do not corroborate each other. TOP500 is the only source for Rmax, Rpeak and core count, so the tier is reported.

Timeline

2018 First operational source
2018-06 List debut at #23 (June 2018) 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

Julich Supercomputing Centre

Location: Julich, Germany
Cooling: Direct liquid cooling
Commissioned: 2004

fz-juelich.de

Where sources disagree

We record conflicts instead of picking a winner quietly. All open questions.

Core count: 122,768 (JSC) against 114,480 (TOP500). JSC includes later additions; TOP500 is used.

Change history

2026-09-22 Gained a Green500 rank pointer (#171 on the 2025-06 list)
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
fz-juelich.de	names system and part	Mellanox InfiniBand EDR
top500.org	names system and part	Mellanox InfiniBand EDR

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