The supercomputer, which was supposed to be ready by the first quarter of 2020 and is intended to be the world's first exascale computing device, has been held up as engineers get to grips with the shift in architecture from Oracle Sparc to ARM, as well as the manufacturing processes required to make the 10nm parts.
The news comes just weeks after ARM unveiled further details of the Scalable Vector Extensions that the firm is developing for the ARMv8-A architecture selected for the project, and which is intended to help drive ARM into high-end servers and supercomputing.
The current K supercomputer Fujitsu built for Japan's RIKEN Advanced Institute for Computational Science is ranked as the fifth most powerful in the world, but runs customised 2GHz Oracle Sparc64 VIIIfx microprocessors, rather than ARM.
Fujitsu publicly admitted the delays yesterday, suggesting that they are down to the time it is taking the design team to get up to speed with "a new CPU-related semiconductor technology". The delay is expected to push back the switch-on date by 12 to 24 months, the company admitted.
It is not clear whether the CPU-related problems cited by Fujitsu are a result of the design team struggling to get to grips with ARM's nascent SVE technology (which is intended to support scalability), applying Fujitsu's Tofu interconnect ported from the K supercomputer to the Post-K design, the 10nm process manufacturing of the CPUs (which will be made by TSMC), or something else entirely.
Fujitsu's Post-K supercomputer is intended to beat the US to become the first public exascale supercomputer. A US government-funded exascale supercomputer has a target date of 2023 for delivery.
It was confirmed earlier this year that China's Sunway TaihuLight supercomputer, featuring 10,649,600 microprocessor cores and compute power of just over 93,000 teraflops, was the world's most powerful supercomputer by a long way ahead of the second-placed design, its predecessor, the Tianhe-2.
The Sunway TaihuLight features a proprietary microprocessor, whereas the Tianhe-2 used Intel Xeon E5s.
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