United Kingdom · operational · hpc

Tursa

Also known as DiRAC Tursa; Extreme Scaling GPU

Operated by EPCC at Advanced Computing Facility, Edinburgh .

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: 5.23 PFlop/s
Rpeak: 8.58 PFlop/s
Rmax ÷ Rpeak: 61.0%
Cores: 55,552
Power: 243.95 kW
Per watt: 21.4 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	- Eviden BullSequana XH2000 (TOP500 manufacturer Bull)	Eviden ATOEPA rolls up to Atos	-	Verified	top500.org epcc.ed.ac.uk
Accelerator	NVIDIA A100 SXM4 40GB Accelerators CUDA (Ampere GA100) · 6,912C · 1.41 GHz · 7 nm · 400 W NVIDIA A100 40GB (114 nodes x 4); 64 further nodes carry A100 80GB	NVIDIA NVDANASDAQ	-	Verified	top500.org epcc.ed.ac.uk
CPU	- AMD EPYC Rome host CPUs (TOP500 7302 32C 3GHz; EPCC 7272 GPU nodes, 7H12 CPU nodes)	AMD AMDNASDAQ	-	Reported	top500.org epcc.ed.ac.uk
Interconnect	NVIDIA InfiniBand HDR Interconnect Fat tree or dragonfly+ · 200 Gb/s per port · About 0.6 microseconds 4x 200 Gbps NVIDIA InfiniBand HDR per GPU node, fat tree	NVIDIA NVDANASDAQ	-	Verified	top500.org epcc.ed.ac.uk
Cooling	Direct liquid cooling, warm water Cooling Direct-to-chip cold plates, facility water loop · Removes 90+ percent of node heat to liquid Water-cooled BullSequana XH2000 racks	Eviden ATOEPA rolls up to Atos	-	Reported	epcc.ed.ac.uk
Operating system	Red Hat Enterprise Linux Operating systems Linux distribution · Open source, commercial support subscription Red Hat Enterprise Linux	Red Hat IBMNYSE rolls up to IBM	-	Reported	epcc.ed.ac.uk

The read

The University of Edinburgh's DiRAC Extreme Scaling GPU system, hosted by EPCC at its Advanced Computing Facility: five water-cooled Eviden BullSequana XH2000 racks holding 184 GPU nodes (114 with four A100-40, 64 with four A100-80) and 6 CPU nodes, four 200 Gbps InfiniBand interfaces per GPU node in a fat tree, 8 PB of DDN Lustre and RHEL. TOP500 lists 55,552 cores of AMD EPYC 7302 with A100 40GB, HDR InfiniBand, Rmax 5.23 PFlop/s, Rpeak 8.58 PFlop/s and 244 kW, installed 2021; EPCC names the GPU-node CPU as EPYC 7272, which conflicts, so the CPU part is left generic. It debuted at 95th on the November 2021 TOP500, its best rank, and was 296th in June 2026.

Timeline

2021 First operational source
2021-11 List debut at #95 (November 2021) source

Public list appearances

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

#95: TOP500, November 2021 →

Site & facility

Advanced Computing Facility, Edinburgh

Location: Edinburgh, United Kingdom
Cooling: Direct liquid cooling
Commissioned: 1990

archer2.ac.uk

Change history

2026-10-02 Added Tursa, the DiRAC Extreme Scaling GPU system at EPCC, 95th 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	NVIDIA A100 SXM4 40GB, NVIDIA InfiniBand HDR
epcc.ed.ac.uk	names system and part	NVIDIA A100 SXM4 40GB, NVIDIA InfiniBand HDR, Direct liquid cooling, warm water

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