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arXiv · 2410.22262

Communication Characterization of AI Workloads for Large-scale Multi-chiplet Accelerators

Mariam Musavi·Emmanuel Irabor·Abhijit Das·Eduard Alarcon·Sergi Abadal
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Abstract

Next-generation artificial intelligence (AI) workloads are posing challenges of scalability and robustness in terms of execution time due to their intrinsic evolving data-intensive characteristics. In this paper, we aim to analyse the potential bottlenecks caused due to data movement characteristics of AI workloads on scale-out accelerator architectures composed of multiple chiplets. Our methodology captures the unicast and multicast communication traffic of a set of AI workloads and assesses aspects such as the time spent in such communications and the amount of multicast messages as a function of the number of employed chiplets. Our studies reveal that some AI workloads are potentially vulnerable to the dominant effects of communication, especially multicast traffic, which can become a performance bottleneck and limit their scalability. Workload profiling insights suggest to architect a flexible interconnect solution at chiplet level in order to improve the performance, efficiency and scalability of next-generation AI accelerators.

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Mariam Musavi, Emmanuel Irabor, Abhijit Das, Eduard Alarcon, Sergi Abadal. 2024-10-29. Communication Characterization of AI Workloads for Large-scale Multi-chiplet Accelerators. https://arxiv.org/abs/2410.22262

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