Hot Chips 2026: Fujitsu’s Monaka CPU

Fujitsu’s A64FX was a pivotal core. For the Arm ecosystem, it introduced SVE. SVE continues to define Arm’s vector execution strategy to this day, with newer extensions like SME adopting a similar vector length agnostic approach. For Fujitsu, A64FX marked a shift away from SPARC and towards the 64-bit Arm ISA (aarch64). Adopting aarch64 let Fujitsu take advantage of a stronger, better supported software ecosystem. Because there’s a lot more Arm software out there than SPARC software, the shift also opened up market opportunities beyond Fujistu’s core competency.However, A64FX was not well suited to general purpose workloads. It ran at a low 2 GHz clock speed, had a small out-of-order engine, and fed that using a comparatively basic branch predictor. That was great for regular HPC code that primarily wants to feed the core’s two 512-bit vector pipes, but would likely not compete well with AMD, Arm, or Intel’s top-of-the-line cores. The latest cores from those manufacturers have large…