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arXiv · 1902.04620

Extreme Tensoring for Low-Memory Preconditioning

Xinyi Chen·Naman Agarwal·Elad Hazan·Cyril Zhang·Yi Zhang
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Abstract

State-of-the-art models are now trained with billions of parameters, reaching hardware limits in terms of memory consumption. This has created a recent demand for memory-efficient optimizers. To this end, we investigate the limits and performance tradeoffs of memory-efficient adaptively preconditioned gradient methods. We propose extreme tensoring for high-dimensional stochastic optimization, showing that an optimizer needs very little memory to benefit from adaptive preconditioning. Our technique applies to arbitrary models (not necessarily with tensor-shaped parameters), and is accompanied by regret and convergence guarantees, which shed light on the tradeoffs between preconditioner quality and expressivity. On a large-scale NLP model, we reduce the optimizer memory overhead by three orders of magnitude, without degrading performance.

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Xinyi Chen, Naman Agarwal, Elad Hazan, Cyril Zhang, Yi Zhang. 2019-02-12. Extreme Tensoring for Low-Memory Preconditioning. https://arxiv.org/abs/1902.04620

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