Papers › Large Memory Layers with Product Keys

Large Memory Layers with Product Keys

10 Jul 2019NeurIPS 2019 12arXiv:1907.05242archive 2025-07-28

Guillaume Lample, Alexandre Sablayrolles, Marc'Aurelio Ranzato, Ludovic Denoyer, Hervé Jégou

This paper introduces a structured memory which can be easily integrated into a neural network. The memory is very large by design and significantly increases the capacity of the architecture, by up to a billion parameters with a negligible computational overhead. Its design and access pattern is based on product keys, which enable fast and exact nearest neighbor search. The ability to increase the number of parameters while keeping the same computational budget lets the overall system strike a better trade-off between prediction accuracy and computation efficiency both at training and test time. This memory layer allows us to tackle very large scale language modeling tasks. In our experiments we consider a dataset with up to 30 billion words, and we plug our memory layer in a state-of-the-art transformer-based architecture. In particular, we found that a memory augmented model with only 12 layers outperforms a baseline transformer model with 24 layers, while being twice faster at inference time. We release our code for reproducibility purposes.

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log lucidrains/product-key-memory/product_key_memory/product_key_memory.py community (archive-listed) ran · our draft was wrong fingerprinted MIT (permissive) · b5472673332de78e · report
default lucidrains/product-key-memory/product_key_memory/product_key_memory.py community (archive-listed) ran · violated contract fingerprinted MIT (permissive) · 60fff7c3c400d7ff · report
eval_decorator lucidrains/product-key-memory/product_key_memory/transformer.py community (archive-listed) ran · our draft was wrong MIT (permissive) · c16aee9490eb8729 · report
exists lucidrains/product-key-memory/product_key_memory/product_key_memory.py community (archive-listed) ran · violated contract MIT (permissive) · aa5486a3650902d8 · report

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Language ModelingLanguage Modelling

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Absolute Position EncodingsAdamAttentionBPEDense ConnectionsDropoutLabel SmoothingLayer NormalizationLinear LayerMulti-Head AttentionPosition-Wise Feed-Forward LayerReLUResidual ConnectionSoftmaxTransformer

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