KEK SR8000-F1/100

Also known as Hitachi SR8000 model F1 at KEK

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: 917.0 GFlop/s
Rpeak: 1.20 TFlop/s
Rmax ÷ Rpeak: 76.4%
Cores: 100
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 built the SR8000 model F1	Hitachi 6501TSE	-	Reported	scwww.kek.jp top500.org
Operating system	Hitachi HI-UX/MPP Operating systems Unix (Mach 3.0 microkernel), Hitachi-customised · Proprietary Hitachi HI-UX/MPP operating system	Hitachi 6501TSE	-	Reported	top500.org

The read

The Hitachi SR8000 model F1 that replaced KEK's VPP500/80. KEK's past-systems page says it ran from March 2000 to December 2005 as 100 compute nodes joined by a very fast network, with 1.2 TFlop/s peak and 444 GB of main memory (448 GB in a second listing), and that it was the fastest supercomputer in Japan when it started. TOP500 agrees on 100 nodes and 1,200 GFlop/s Rpeak and adds 917 GFlop/s Rmax under HI-UX/MPP on a multi-dimensional crossbar, sixth on the June 2000 list, last listed at rank 456 in November 2004 (https://www.top500.org/system/170748/). TOP500 is the only source for Rmax, so the tier is reported.

Timeline

2000-03 First operational source
2000-06 List debut at #6 (June 2000) source
2005-12 Decommissioned source

Public list appearances

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

#6: TOP500, June 2000 →

Site & facility

KEK Tsukuba Campus

Location: Tsukuba, Japan

scwww.kek.jp

Change history

2026-10-09 Added KEK SR8000-F1/100

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
scwww.kek.jp	does not name this system	Hitachi HI-UX/MPP
top500.org	names system and part	Hitachi HI-UX/MPP

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