Learning Structured Sparsity in Deep Neural Networks

TL;DR

This paper introduces Structured Sparsity Learning (SSL), a method to optimize DNN structures for reduced computation and improved efficiency, achieving significant speedups and accuracy improvements on benchmark datasets.

Contribution

SSL is a novel regularization technique that learns compact, hardware-friendly DNN structures, enabling faster inference and better accuracy compared to traditional methods.

Findings

Achieves 5.1x and 3.1x speedups on AlexNet for CPU and GPU.

Reduces ResNet layers from 20 to 18 with improved accuracy.

Improves AlexNet error rate by approximately 1%.

Abstract

High demand for computation resources severely hinders deployment of large-scale Deep Neural Networks (DNN) in resource constrained devices. In this work, we propose a Structured Sparsity Learning (SSL) method to regularize the structures (i.e., filters, channels, filter shapes, and layer depth) of DNNs. SSL can: (1) learn a compact structure from a bigger DNN to reduce computation cost; (2) obtain a hardware-friendly structured sparsity of DNN to efficiently accelerate the DNNs evaluation. Experimental results show that SSL achieves on average 5.1x and 3.1x speedups of convolutional layer computation of AlexNet against CPU and GPU, respectively, with off-the-shelf libraries. These speedups are about twice speedups of non-structured sparsity; (3) regularize the DNN structure to improve classification accuracy. The results show that for CIFAR-10, regularization on layer depth can reduce 20 layers of a Deep Residual Network (ResNet) to 18 layers while improve the accuracy from 91.25% to 92.60%, which is still slightly higher than that of original ResNet with 32 layers. For AlexNet, structure regularization by SSL also reduces the error by around ~1%. Open source code is in https://github.com/wenwei202/caffe/tree/scnn