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Spiking Neural Networks (SNNs) are an emerging computation model that uses event-driven activation and bio-inspired learning algorithms. SNN-based machine learning programs are typically executed on tile-based neuromorphic hardware platforms, where each tile consists of a computation unit called a crossbar, which maps neurons and synapses of the program. However, synthesizing such programs on an off-the-shelf neuromorphic hardware is challenging. This is because of the inherent resource and latency limitations of the hardware, which impact both model performance, e.g., accuracy, and hardware performance, e.g., throughput. We propose DFSynthesizer, an end-to-end framework for synthesizing SNN-based machine learning programs to neuromorphic hardware. The proposed framework works in four steps. First, it analyzes a machine learning program and generates SNN workload using representative data. Second, it partitions the SNN workload and generates clusters that fit on crossbars of the target neuromorphic hardware. Third, it exploits the rich semantics of the Synchronous Dataflow Graph (SDFG) to represent a clustered SNN program, allowing for performance analysis in terms of key hardware constraints such as number of crossbars, dimension of each crossbar, buffer space on tiles, and tile communication bandwidth. Finally, it uses a novel scheduling algorithm to execute clusters on crossbars of the hardware, guaranteeing hardware performance. We evaluate DFSynthesizer with 10 commonly used machine learning programs. Our results demonstrate that DFSynthesizer provides a much tighter performance guarantee compared to current mapping approaches.
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Clustering and Allocation of Spiking Neural Networks on Crossbar-Based Neuromorphic Architecture
Neuromorphic hardware, designed to mimic the neural structure of the human brain, offers an energy-efficient platform for implementing machine-learning models in the form of Spiking Neural Networks (SNNs). Achieving efficient SNN execution on this hardware requires careful consideration of various objectives, such as optimizing utilization of individual neuromorphic cores and minimizing inter-core communication. Unlike previous approaches that overlooked the architecture of the neuromorphic core when clustering the SNN into smaller networks, our approach uses architecture-aware algorithms to ensure that the resulting clusters can be effectively mapped to the core. We base our approach on a crossbar architecture for each neuromorphic core. We start with a basic architecture where neurons can only be mapped to the columns of the crossbar. Our technique partitions the SNN into clusters of neurons and synapses, ensuring that each cluster fits within the crossbar's confines, and when multiple clusters are allocated to a single crossbar, we maximize resource utilization by efficiently reusing crossbar resources. We then expand this technique to accommodate an enhanced architecture that allows neurons to be mapped not only to the crossbar's columns but also to its rows, with the aim of further optimizing utilization. To evaluate the performance of these techniques, assuming a multi-core neuromorphic architecture, we assess factors such as the number of crossbars used and the average crossbar utilization. Our evaluation includes both synthetically generated SNNs and spiking versions of well-known machine-learning models: LeNet, AlexNet, DenseNet, and ResNet. We also investigate how the structure of the SNN impacts solution quality and discuss approaches to improve it.
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- Award ID(s):
- 2209745
- PAR ID:
- 10535579
- Publisher / Repository:
- ACM
- Date Published:
- ISBN:
- 9798400705977
- Page Range / eLocation ID:
- 164 to 171
- Format(s):
- Medium: X
- Location:
- Ischia Italy
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3649153.3649199
