• wewbull
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    6 months ago

    I think those will have to have fairly good IPC, otherwise they won’t be able to keep the array processors fed with work.

    Guess we’ll see.

    • barsoap@lemm.ee
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      6 months ago

      You can keep the array processors fed with low IPC and frequency by having absolutely massive vector lengths, the engineering for that kind of processor isn’t in the pipeline, branch prediction etc. it’s in the APUs and how to stream data into them. Much more like GPUs, in fact RISC-V has instructions for gather/scatter.

      • wewbull
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        6 months ago

        Disagree. You quite often have a fair degree of scaler code in between portions which are embarrassingly parallel. If you don’t have a decent scaler core you are destined to be become bottlenecked on them. It’s not that different to a CPU / GPU pairing. If one is under powered, it determines the speed of the overall system.

        If you look at what a company like Tenstorrent is doing, they are designing high performance Risc-V cores as a side aspect of their main goal of doing array processors. The reason is because they couldn’t find scaler cores on the market with enough performance to not bottleneck the system.