Deep neural networks are increasingly required to operate across diverse hardware platforms, latency constraints, and power budgets, which motivates the need for specialized models for each scenario. However, designing and training a separate model per scenario or serving a large ensemble of models is often impractical. Weight sharing has emerged as a promising paradigm to address this challenge by training a single ''SuperNet'' that subsumes many sub-models (SubNets), and by reusing weights across those SubNets both at training and inference time. This paper provides an abridged survey of our recent advances that leverage weight sharing for efficient AI, covering both training and inference serving. In centralized once-for-all training, Delayed ε-Shrinking (DεS) improves training efficiency by strategically scheduling the introduction of smaller SubNets during training. In a federated fashion, SuperFedNas co-trains a SuperNet across distributed clients and disjoins training and searching, which enables oneshot specialization to many deployment targets at minimal cost. ∇QDARTS integrates quantization into differentiable architecture search, jointly finding neural architectures, weights, and low-precision settings to yield highly efficient models in a single search. For inference serving, SuperServe introduces a weight-shared model with dynamic SubNet routing (SubNetAct) to instantaneously switch among a spectrum of accuracy-latency operating points, coupled with a scheduler (SlackFit) for unpredictable workloads. Finally, SUSHI co-designs model, system, and accelerator to exploit weightshared SuperNets on tinyML devices, caching SubGraphs on FPGA to reduce latency and energy. Together, these works demonstrate that the weight sharing paradigm can dramatically improve the efficiency of both training and inference serving of deep models across a range of scenarios.
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Hardware–Software Co-Design for Real-Time Latency–Accuracy Navigation in Tiny Machine Learning Applications
Tiny machine learning (TinyML) applications increasingly operate in dynamically changing deployment scenarios, requiring optimization for both accuracy and latency. Existing methods mainly target a single point in the accuracy/latency tradeoff space, which is insufficient as no single static point can be optimal under variable conditions. We draw on a recently proposed weight-shared SuperNet mechanism to enable serving a stream of queries that activates different SubNets within a SuperNet. This creates an opportunity to exploit the inherent temporal locality of different queries that use the same SuperNet. We propose a hardware–software co-design called SUSHI that introduces a novel SubGraph Stationary optimization. SUSHI consists of a novel field-programmable gate array implementation and a software scheduler that controls which SubNets to serve and which SubGraph to cache in real time. SUSHI yields up to a 32% improvement in latency, 0.98% increase in served accuracy, and achieves up to 78.7% off-chip energy saved across several neural network architectures.
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- Award ID(s):
- 2029004
- PAR ID:
- 10510165
- Publisher / Repository:
- IEEE Computer Society
- Date Published:
- Journal Name:
- IEEE Micro
- Volume:
- 43
- Issue:
- 6
- ISSN:
- 0272-1732
- Page Range / eLocation ID:
- 93 to 101
- Subject(s) / Keyword(s):
- Training, Real Time Systems, Optimization, Neural Networks, System On Chip, Software, Tiny Machine Learning, Machine Learning, Microcontrollers, Software Design, Machine Learning Applications, Tiny Machine Learning, Neural Network, Deep Neural Network, Search Space, Autonomous Vehicles, Design Space, Self Driving, Temporal Localization, Caching, Data Reuse, Neural Architecture Search, Deployment Phase, Improvement In Latency, Blue Dots, Dot Product, Load Data, Latency Reduction, Cache Hit, Shared Weights
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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