Papers › AC/DC: Alternating Compressed/DeCompressed Training of Deep Neural Networks

AC/DC: Alternating Compressed/DeCompressed Training of Deep Neural Networks

23 Jun 2021NeurIPS 2021 12arXiv:2106.12379archive 2025-07-28

Alexandra Peste, Eugenia Iofinova, Adrian Vladu, Dan Alistarh

The increasing computational requirements of deep neural networks (DNNs) have led to significant interest in obtaining DNN models that are sparse, yet accurate. Recent work has investigated the even harder case of sparse training, where the DNN weights are, for as much as possible, already sparse to reduce computational costs during training. Existing sparse training methods are often empirical and can have lower accuracy relative to the dense baseline. In this paper, we present a general approach called Alternating Compressed/DeCompressed (AC/DC) training of DNNs, demonstrate convergence for a variant of the algorithm, and show that AC/DC outperforms existing sparse training methods in accuracy at similar computational budgets; at high sparsity levels, AC/DC even outperforms existing methods that rely on accurate pre-trained dense models. An important property of AC/DC is that it allows co-training of dense and sparse models, yielding accurate sparse-dense model pairs at the end of the training process. This is useful in practice, where compressed variants may be desirable for deployment in resource-constrained settings without re-doing the entire training flow, and also provides us with insights into the accuracy gap between dense and compressed models. The code is available at: https://github.com/IST-DASLab/ACDC .

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GradualNormPrunerSGD IST-DASLab/ACDC/optimization/gradual_norm_reduction_pruner.py official repository ran Apache-2.0 (permissive) · bd353d9bbcb08c1e · report
SparseConvFunction IST-DASLab/sparseprop/sparseprop/modules/conv2d.py community (archive-listed) ran Apache-2.0 (permissive) · 1e358405d88a676c · report
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Tasks

Network Pruning

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Network Pruning CIFAR-100 Dense Accuracy 79 #1 of 5 Archive leaderboard report
Network Pruning CIFAR-100 AC/DC Accuracy 78.2 #2 of 5 Archive leaderboard report
Network Pruning ImageNet ResNet50 Accuracy 73.14 #14 of 16 Archive leaderboard report
Network Pruning ImageNet - ResNet 50 - 90% sparsity AC/DC Top-1 Accuracy 75.64 #4 of 9 Archive leaderboard report

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