Mixture-of-Rookies: saving DNN computations by predicting ReLU outputs

Deep Neural Networks (DNNs) are widely used in many application domains. However, they require a vast amount of computations and memory accesses to deliver outstanding accuracy. In this paper, we propose a scheme to predict whether the output of each ReLu activated neuron will be a zero or a positiv...

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Bibliographic Details
Authors: Pinto Rivero, Dennis|||0000-0002-2175-9580, Arnau Montañés, José María|||0000-0002-0336-9191, Riera Villanueva, Marc|||0000-0002-2768-5703, Cruz Díaz, Josep Llorenç|||0000-0001-5325-9153, González Colás, Antonio María|||0000-0002-0009-0996
Format: article
Publication Date:2024
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/416829
Online Access:https://hdl.handle.net/2117/416829
https://dx.doi.org/10.1016/j.micpro.2024.105087
Access Level:Open access
Keyword:Neural networks
Energy efficiency
Cognitive computing
Hardware acceleration
Àrees temàtiques de la UPC::Informàtica::Arquitectura de computadors
Description
Summary:Deep Neural Networks (DNNs) are widely used in many application domains. However, they require a vast amount of computations and memory accesses to deliver outstanding accuracy. In this paper, we propose a scheme to predict whether the output of each ReLu activated neuron will be a zero or a positive number in order to skip the computation of those neurons that will likely output a zero. Our predictor, named Mixture-of-Rookies, combines two inexpensive components. The first one exploits the high linear correlation between binarized (1-bit) and full-precision (8-bit) dot products, whereas the second component clusters together neurons that tend to output zero at the same time. We propose a novel clustering scheme based on analysis of angles, as the sign of the dot product of two vectors depends on the cosine of the angle between them. We implement our hybrid zero output predictor on top of a state-of-the-art DNN accelerator. Experimental results show that our scheme introduces a small area overhead of 5.3% while achieving a speedup of 1.2x and reducing energy consumption by 16.5% on average for a set of diverse DNNs.