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arXiv · 2407.20537

Switchboard: An Open-Source Framework for Modular Simulation of Large Hardware Systems

Steven Herbst·Noah Moroze·Edgar Iglesias·Andreas Olofsson
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Abstract

Scaling up hardware systems has become an important tactic for improving performance as Moore's law fades. Unfortunately, simulations of large hardware systems are often a design bottleneck due to slow throughput and long build times. In this article, we propose a solution targeting designs composed of modular blocks connected by latency-insensitive interfaces. Our approach is to construct the hardware simulation in a similar fashion as the design itself, using a prebuilt simulator for each block and connecting the simulators via fast shared-memory queues at runtime. This improves build time, because simulation scale-up simply involves running more instances of the prebuilt simulators. It also addresses simulation speed, because prebuilt simulators can run in parallel, without fine-grained synchronization or global barriers. We introduce a framework, Switchboard, that implements our approach, and discuss two applications, demonstrating its speed, scalability, and accuracy: (1) a web application where users can run fast simulations of chiplets on an interposer, and (2) a wafer-scale simulation of one million RISC-V cores distributed across thousands of cloud compute cores.

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Steven Herbst, Noah Moroze, Edgar Iglesias, Andreas Olofsson. 2024-07-30. Switchboard: An Open-Source Framework for Modular Simulation of Large Hardware Systems. https://arxiv.org/abs/2407.20537

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