IBM Linux cluster - Lightning
On July 12, 2004, NCAR's Scientific Computing Division (SCD) took delivery of "Lightning," a large-scale, high-performance Linux cluster manufactured by IBM. The acquisition was part of SCD's five-year Strategic Plan to evaluate new technologies and find ways for SCD to deliver more cost-effective tools for advancing the frontiers of science at NCAR; as such, it was NCAR's first Linux-based supercomputer.
The 1.1-teraflop system was considerably faster on a per-processor basis than Bluesky, which was at the time NCAR's flagship IBM p690 system. In benchmark tests, the Community Atmosphere Model (CAM) tests ran 30% faster, while the Parallel Ocean Program (POP) ran 40% faster, than on Bluesky. One reason for this was that Lightning's Opteron processors, built by Advanced MicroDevices (AMD), had better memory bandwidth than Bluesky's Power4 processors, and thus could run these 'data-hungry' models more efficiently.
At the time, many of NCAR's university partners who used models such as the Community Climate System Model (CCSM) or the Weather Research and Forecast (WRF) model had Linux-based systems. Lightning offered them, for the first time at NCAR, the chance to build, test, and evaluate these codes in a full-scale Linux computing environment similar to their own.