Supercomputers/Systems/KEK Blue Gene System B
Japan · operational · hpc
KEK Blue Gene System B
Also known as KEK/BG Sakura; KEK/BG MOMO; KEK/BG UME
Operated by KEK at KEK Tsukuba Campus .
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
- -
- Rpeak
- 57.30 TFlop/s
- Rmax ÷ Rpeak
- -
- Cores
- 20,480
- 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 | - IBM System Blue Gene Solution, 10 racks of 1,024 nodes | IBM | - | Reported | scwww.kek.jptop500.org |
| CPU | IBM PowerPC 440 700MHz CPUs PowerPC · 2C · 0.7 GHz · 130 nm · 13 W IBM PowerPC 440 700 MHz | IBM | - | Reported | top500.org |
The read
System B of KEK's 2006 to 2011 central computing complex: an IBM System Blue Gene Solution of 10 racks with 1,024 nodes each, 5.12 TB of memory and a stated 57.3 Tflops total, in service from March 2006 beside the Hitachi SR11000 model K1 general-purpose System A (16 nodes, 2.15 Tflops) over shared storage, per KEK's Japanese-language past-systems page; it was succeeded by the Blue Gene/Q record kek-sakura. TOP500 splits the machine into three entries named KEK/BG Sakura (8,192 cores, 22.94 TFlop/s peak), KEK/BG MOMO (8,192 cores, 22.94) and KEK/BG UME (4,096 cores, 11.47), all PowerPC 440 700 MHz with Rmax of 18.66, 18.66 and 9.43 TFlop/s and stated draws of 89, 89 and 44 kW. The three peaks sum to 57.35 TFlop/s and 20,480 cores, which agrees with KEK's 57.3 Tflops, and that sum is what is recorded as the peak; no combined Rmax exists because the parts were run separately. Sakura and MOMO ranked 17th and 18th in June 2006, so no single list rank is recorded for the whole machine and ranked is 0. Same node architecture as blue-protein-aist.
Timeline
- 2006-03 First operational source
Site & facility
Change history
- 2026-10-17 KEK Blue Gene System B added from its source pages
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.
Every source cited on this page was readable, and none of them mentions this system. They are cited at page granularity, normally because no stable deep link could be found. That is a real weakness in this row and it is why the system carries a confidence tier below verified. See how this check works.
| Cited source | Result | Found on the page |
|---|---|---|
| scwww.kek.jp | does not name this system | - |
| top500.org | does not name this system | IBM PowerPC 440 700MHz |
Checked 2026-10-18 by pnpm verify. Re-run it and the table changes with the web.