The three Japanese supercomputer vendors have decided to offer different architectures to their customers: Fujitsu follows along the path of distributed memory, proprietary vector processor systems started with their VPP500 range; Hitachi offers MPP systems based on commodity RISC processors (HP variety) besides their older shared memory, proprietary vector processor system S3800, while NEC markets a cluster of shared memory, proprietary vector processor systems with up to 32 processors per cluster node.
Fujitsu and NEC continue to build fast vector machines employing tested designs. Both have succeeded in building their machines using the latest .35 micron CMOS technology, but differ with regard to the memory architecture. Fujitsu believes in large, distributed, relatively slow memory (SDRAM), while NEC uses smaller, very fast, shared memory (SSRAM) for its cluster nodes. Otherwise, the processors of the two competitors are remarkably similar with a performance of 2.2 resp. 2 GFlops/s achieved with 8 vector pipes.
Hitachi follows the route developed by the MPP RISC protagonists, such as IBM, Intel, Meiko, TMC and more recently CRI. They use commodity RISC chips with their own connecting network. Since Hitachi only came to market in 1994 with its first generation of machines, it is at a disadvantage compared to its competitors who by now deliver at least their second generation of systems. Consequently, the market penetration of Hitachi is so far restricted to a few development sites. However, considering the size of Hitachi and its probable long-term plans, the future Hitachi MPP systems may become formidable competitors world-wide.