Switzerland · decommissioned · mixed

Piz Daint

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: 21.23 PFlop/s
Rpeak: 27.15 PFlop/s
Rmax ÷ Rpeak: 78.2%
Cores: 387,872
Power: 2.38 MW
Per watt: 8.9 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	- Cray XC50	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	cscs.ch hpe.com
Accelerator	NVIDIA Tesla P100 Accelerators CUDA (Pascal GP100) · 3,584C · 1.48 GHz · 16 nm · 300 W NVIDIA Tesla P100	NVIDIA NVDANASDAQ	-	Reported	cscs.ch hpe.com
CPU	Intel Xeon E5-2690 v3 CPUs x86-64 · 12C · 2.6 GHz · 22 nm · 135 W Xeon E5-2690v3 12C 2.6GHz	Intel INTCNASDAQ	-	Reported	cscs.ch hpe.com
Interconnect	Cray Aries Interconnect Dragonfly · About 10 GB/s per direction · Around 1 microsecond Aries interconnect	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	cscs.ch hpe.com
Storage	Lustre Storage Parallel filesystem, separate metadata and object servers Sonexion 3000 Storage Capacity 6.2 PB and Sonexion 1600 Storage Capacity 2.5 PB	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	cscs.ch
Cooling	Liquid-assisted air (in-cabinet coil) Cooling In-cabinet air, water-cooled coil · Roughly 20-45 kW per cabinet Cray XC50 cabinet: transverse air across in-cabinet water coils	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	cscs.ch hpe.com
Operating system	Cray Linux Environment Operating systems Linux, Cray-customised · Proprietary layer over open-source Linux Cray Linux Environment	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	cscs.ch hpe.com

The read

Europe's fastest system for several years, and the direct predecessor of Alps on the same site. Cray XC50 with one P100 per node; the site retained the building, the lake-water cooling and the operator, and replaced everything else - which is what a refresh cycle actually looks like at the facility layer.

Timeline

2012 Announced source
2017-06 List debut at #3 (June 2017) source
2017-06 First operational source
2023 Decommissioned source
2025-01 Physically shut down for the last time, about two years after Alps took over production workloads 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

CSCS, Lugano

Location: Lugano, Switzerland
Cooling: Lake-water cooling (Lake Lugano)
Commissioned: 2012

cscs.ch

Change history

2026-09-22 Gained a Green500 rank pointer (#68 on the 2023-11 list)

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
cscs.ch	names system and part	NVIDIA Tesla P100, Intel Xeon E5-2690 v3, Cray Aries
hpe.com	does not name this system	Lustre

Checked 2026-10-13 by pnpm verify. Re-run it and the table changes with the web.

Related news

2025-01-23 Piz Daint powered off after 13 years, cleared for Alps · CSCS
CSCS retired the Cray XC50/XC40 system that had anchored Swiss GPU computing since 2012, closing out the last pre Grace Hopper system in this dataset's Swiss lineage and completing the multi year handover to Alps that began with Alps' 2024 inauguration.

All news →