Supercomputers/Systems/Lemhi
USA · decommissioned · hpc
Lemhi
Also known as INL Lemhi
Operated by INL .
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
- 1.00 PFlop/s
- Rpeak
- 1.55 PFlop/s
- Rmax ÷ Rpeak
- 64.5%
- Cores
- 20,160
- Power
- 219.5 kW
- Per watt
- 4.6 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 | - Dell PowerEdge C6420, 504 nodes | Dell Technologies | - | Reported | top500.orgdocs.c3plus3.org |
| CPU | Intel Xeon Gold 6148 CPUs x86-64 · 20C · 2.4 GHz · 14 nm · 150 W Intel Xeon Gold 6148 20C 2.4GHz, two per node | Intel | - | Reported | top500.orgdocs.c3plus3.org |
| Interconnect | Omni-Path Architecture Interconnect Fat tree · 100 Gb/s per port · About 1 microsecond Intel Omni-Path | Cornelis Networks | - | Reported | top500.orgdocs.c3plus3.org |
| Operating system | CentOS Operating systems Linux distribution, RHEL-compatible rebuild · Open source, community-maintained CentOS | The CentOS Project | - | Reported | top500.org |
The read
Idaho National Laboratory's 504-node Dell PowerEdge C6420 cluster purchased in 2018 as the successor to Falcon, with dual Intel Xeon Gold 6148 20-core processors per node, 192 GB of memory per node and an Omni-Path fabric. TOP500 lists 20,160 cores, Rmax 1.00 PFlop/s, Rpeak 1.55 PFlop/s and 219.5 kW under CentOS; it appeared only on the November 2018 list, at rank 427. The documentation of the C3+3 collaboration (University of Idaho, Boise State and Idaho State) says INL turned the hardware over to the three universities in April 2025, rebuilt on Rocky Linux 8.10, so INL's own service is recorded as ending then although the cluster continues under the universities. The INL site is not named in a fetched page, so no site is recorded.
Timeline
- 2018 First operational source
- 2018-11 List debut at #427 (November 2018) source
- 2025-04 Decommissioned source
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Change history
- 2026-10-07 Added Lemhi, Idaho National Laboratory's Dell 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 |
|---|---|---|
| docs.c3plus3.org | names system and part | Intel Xeon Gold 6148, Omni-Path Architecture |
| top500.org | names system and part | Intel Xeon Gold 6148, Omni-Path Architecture, CentOS |
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.