[ICLR 2020] Drawing Early-Bird Tickets: Towards More Efficient Training of Neural Networks

Accepted as spotlight oral paper!


Abstract:

(Frankle & Carbin, 2019) shows that there exist winning tickets (small but critical subnetworks) for dense, randomly initialized networks, that can be trained alone to achieve comparable accuracies to the latter in a similar number of iterations. However, the identification of these winning tickets still requires the costly train-prune-retrain process, limiting their practical benefits. In this paper, we discover for the first time that the winning tickets can be identified at the very early training stage, which we term as early-bird (EB) tickets, via low-cost training schemes (e.g., early stopping and low-precision training) at large learning rates. Our finding of EB tickets is consistent with recently reported observations that the key connectivity patterns of neural networks emerge early. Furthermore, we propose a mask distance metric that can be used to identify EB tickets with low computational overhead, without needing to know the true winning tickets that emerge after the full training. Finally, we leverage the existence of EB tickets and the proposed mask distance to develop efficient training methods, which are achieved by first identifying EB tickets via low-cost schemes, and then continuing to train merely the EB tickets towards the target accuracy. Experiments based on various deep networks and datasets validate: 1) the existence of EB tickets, and the effectiveness of mask distance in efficiently identifying them; and 2) that the proposed efficient training via EB tickets can achieve up to 4.7x energy savings while maintaining comparable or even better accuracy, demonstrating a promising and easily adopted method for tackling cost-prohibitive deep network training.


Code now is available at https://github.com/RICE-EIC/Early-Bird-Tickets !


Bibtex

If you find this work inspiring, please cite:

@inproceedings{
you2020drawing,
title={Drawing Early-Bird Tickets: Toward More Efficient Training of Deep Networks},
author={Haoran You and Chaojian Li and Pengfei Xu and Yonggan Fu and Yue Wang and Xiaohan Chen and Yingyan Lin and Zhangyang Wang and Richard G. Baraniuk},
booktitle={International Conference on Learning Representations},
year={2020},
url={https://openreview.net/forum?id=BJxsrgStvr}
}