Supercomputers/Systems/Iridis 5
United Kingdom · operational · hpc
Iridis 5
Operated by University of Southampton at University of Southampton (Iridis) .
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
- 860.00 TFlop/s
- Rpeak
- 1.31 PFlop/s
- Rmax ÷ Rpeak
- 65.6%
- Cores
- 20,400
- 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 | - Lenovo ThinkSystem SD530 nodes (TOP500) | Lenovo | - | Reported | top500.org |
| Accelerator | NVIDIA Tesla V100 Accelerators CUDA (Volta GV100) · 5,120C · 1.53 GHz · 12 nm · 300 W 20 NVIDIA Tesla V100 16 GB cards | NVIDIA | 20 reported | Reported | southampton.ac.uk |
| Accelerator | - 40 NVIDIA GTX 1080 Ti 12 GB cards | NVIDIA | 40 reported | Reported | southampton.ac.uk |
| CPU | - Intel Xeon Gold 6138 20C 2.0GHz: 464 dual-socket Intel nodes (arithmetic from node count) | Intel | 928 estimated | Reported | southampton.ac.uktop500.org |
| Interconnect | Mellanox InfiniBand EDR Interconnect Fat tree · 100 Gb/s per 4x port · About 0.9 microseconds InfiniBand EDR (TOP500); Southampton page now cites HDR100 | NVIDIA | - | Reported | top500.orgsouthampton.ac.uk |
| Storage | - 2.2 PB IBM Spectrum Scale file system | IBM | - | Reported | southampton.ac.uk |
The read
The University of Southampton's fifth-generation Iridis HPC cluster, a Lenovo ThinkSystem SD530 system with Xeon Gold 6138 20C CPUs on InfiniBand EDR. TOP500 lists 20,400 cores, 0.86 PFLOPS Rmax and 1.31 PFLOPS Rpeak, ranking it 252nd in November 2017 and 354th in June 2018. Southampton's facility page describes 464 dual-socket Intel nodes, AMD nodes, 20 NVIDIA V100 and 40 GTX 1080 Ti GPUs, 16 high-memory nodes with 1.5 TB RAM, HDR100 InfiniBand and 2.2 PB of IBM Spectrum Scale storage.
Timeline
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Site & facility
Change history
- 2026-10-02 Added Iridis 5, Southampton's Lenovo Skylake cluster
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 |
|---|---|---|
| southampton.ac.uk | names system, part and count | Mellanox InfiniBand EDR · counts: 20 |
| top500.org | names system, part and count | Mellanox InfiniBand EDR · counts: 20 |
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.