Supercomputers/Systems/Cambridge Hitachi SR2201/96
United Kingdom · operational · hpc
Cambridge Hitachi SR2201/96
Also known as University of Cambridge SR2201
Operated by University of Cambridge .
Researched with AI assistance, checked by scripts. These rows were researched by AI agents reading public operator, laboratory and vendor sources, appended by scripts and checked by automated validation; no subject-matter expert has reviewed them (how this site is made). A mechanical second-reader pass has since fetched every cited source: 1350 of 1540 systems have a readable citation that names them, and 64 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
- 22.2 GFlop/s
- Rpeak
- 28.8 GFlop/s
- Rmax ÷ Rpeak
- 77.0%
- Cores
- 96
- 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 | - Hitachi SR2201/96 | Hitachi | - | Reported | top500.orgtimeshighereducation.com |
| CPU | Hitachi SR2201 processing unit CPUs PA-RISC 1.1 · 1C · 0.15 GHz Hitachi SR2201 HARP-1E 150 MHz, 96 processing units | Hitachi | 96 reported | Reported | top500.orgtimeshighereducation.com |
| Interconnect | Hitachi 3D hyper-crossbar Interconnect 3D hyper-crossbar · 300 MB/s point to point Hyper crossbar | Hitachi | - | Reported | top500.org |
| Operating system | Hitachi HI-UX/MPP Operating systems Unix (Mach 3.0 microkernel), Hitachi-customised · Proprietary HI-UX/MPP | Hitachi | - | Reported | top500.org |
The read
Hitachi SR2201 with 96 HARP-1E 150 MHz processors on the 3-D hyper-crossbar, running HI-UX/MPP, at the University of Cambridge, Rmax 22.18 and Rpeak 28.8 GFlop/s (https://www.top500.org/system/170746/, a single appearance at rank 112 in June 1997). Times Higher Education reported on 12 July 1996 that a new SR2201 with 96 nodes of 256 MB and 300 MFlop/s each would be delivered to Cambridge at the end of September for the science and engineering departments at a cost of about 2.5 million pounds under a complex financing deal. TOP500 splits the Cambridge SR2201 into three entries: 64 cores in November 1996 (https://www.top500.org/system/170740/, rank 119), this 96-core stage in June 1997, and 256 cores from November 1998 to November 2000 (https://www.top500.org/system/170736/, Rmax 58.68 GFlop/s), which look like successive stages of one growing machine. TOP500 gives 1997 as the installation year for the 96-core entry while the press piece implies delivery in autumn 1996, so only the year 1996 is given as the start. The other SR2201 in the dataset is sr2201-tokyo.
Timeline
Public list appearances
Pointers only: rank and edition, linking to the canonical entry. We do not reproduce list tables. See sourcing policy.
Change history
- 2026-10-18 Added Cambridge Hitachi SR2201/96 (university-of-cambridge)
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.