As one of the main driving forces behind the RISC-V architecture, SiFive tends to introduce and showcase RISC-V solutions not available from anyone else in the industry. This week the company demonstrated the industry's first RISC-V cluster that could be used for high-performance computing.
The four-way cluster built by AB Open is based on four SiFive HiFive Unmatched developer motherboards each featuring a Freedom U740 system-on-chip for compute tasks as well as a SiFive HiFive1 Rev. B development board providing control of four relays used to power on/off the four boards. Each HiFive Unmatched motherboard with the Freedom U740 SoC is an individual system that can run high-level operating systems and is equipped with PCIe 3.0 x8/16 and M.2 slots as well as GbE and USB ports.
The Freedom U740 SoC barely offers decent performance for modern HPC applications, but SiFive has the capability to build SoCs with up to 128 high-performance cores. Companies that are interested in designing or using such processors need to ensure that they have proper software for RISC-V, and these boards should help drive the development of such apps.
Since the intention was to build a relatively powerful rackmount system with multiple RISC-V processors (which were never meant to support symmetric multiprocessor technology) and convenient controls, an additional motherboard for controls was needed. That board is connected to a PSU and manages the power distribution to fans and supply sequencing for the HiFive Unmatched boards, each of which is connected to an individual Pico-ATX power supply. Also, the control board connects each GbE port, thus enabling their remote control.
AB Open and SiFive say that the cluster can be used for typical data center or office workloads, but its main purpose is to enable software development and testing. Those who want to try using RISC-V for HPC applications can use multiple clusters to build farms and take advantage of multiple RISC-V cores.