Met Office Cray XC40

Also known as Met Office Exeter XC40; UKMO Cray XC40

Operated by Met Office at Met Office Supercomputer Hall (Exeter) .

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: 7.04 PFlop/s
Rpeak: 8.13 PFlop/s
Rmax ÷ Rpeak: 86.6%
Cores: 241,920
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	- Cray XC40	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	top500.org theregister.com
CPU	Intel Xeon E5-2695 v4 CPUs x86-64 · 18C · 2.1 GHz · 14 nm · 120 W Intel Xeon E5-2695v4 18C 2.1 GHz	Intel INTCNASDAQ	-	Reported	top500.org
Interconnect	Cray Aries Interconnect Dragonfly · About 10 GB/s per direction · Around 1 microsecond Cray Aries interconnect (Dragonfly)	Cray HPENYSE rolls up to Hewlett Packard Enterprise	-	Reported	top500.org theregister.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	top500.org

The read

The largest of the three Cray XC40 systems the UK Met Office ran at Exeter before moving to an Azure-hosted supercomputer: 241,920 cores of Xeon E5-2695v4 18C 2.1 GHz on the Aries interconnect, 7.04 PFlop/s Rmax and 8.13 PFlop/s Rpeak, ranked 11 in November 2016 and still listed in June 2025 at 190. The £97 million order was announced in October 2014 for 16 petaflops across a three-phase rollout (2015 to 2017); two smaller 89,856-core XC40 entries (2.80 PFlop/s Rmax each) are also on TOP500 and are not recorded separately. A March 2025 local news report calls the nine-year-old XC40 the machine being replaced by the off-site Microsoft facility, and the Met Office reports its operational forecasts moved to the Azure supercomputer in May 2025, recorded here only as 2025. The existing Met Office Azure Supercomputer row covers the successor.

Timeline

2014 Announced source
2016 First operational source
2016-11 List debut at #11 (November 2016) source
2025 Decommissioned source

Public list appearances

Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.

#11: TOP500, November 2016 →

Site & facility

Met Office Supercomputer Hall (Exeter)

Location: Exeter, United Kingdom
Commissioned: 2017

theregister.com exeterobserver.org

Change history

2026-10-02 Added Met Office Cray XC40

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	Intel Xeon E5-2695 v4, Cray Aries, Cray Linux Environment
theregister.com	names system and part	Cray Aries, Cray Linux Environment

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