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Intriguing Properties of Quantization at Scale (arxiv.org)
2 points by Jimmc414 on May 31, 2023 | hide | past | pdf | discuss on HN

In plain words: Quantization stores a model's numbers with fewer bits, which usually wrecks performance in big models. A training recipe that keeps activation values from spiking avoided that drop, letting models up to 52B parameters shrink with minimal accuracy loss.

Abstract

Emergent properties have been widely adopted as a term to describe behavior not present in smaller models but observed in larger models. Recent work suggests that the trade-off incurred by quantization is also an emergent property, with sharp drops in performance in models over 6B parameters. In this work, we ask "are quantization cliffs in performance solely a factor of scale?" Against a backdrop of increased research focus on why certain emergent properties surface at scale, this work provides a useful counter-example. We posit that it is possible to optimize for a quantization friendly training recipe that suppresses large activation magnitude outliers. Here, we find that outlier dimensions are not an inherent product of scale, but rather sensitive to the optimization conditions present during pre-training. This both opens up directions for more efficient quantization, and poses the question of whether other emergent properties are inherent or can be altered and conditioned by optimization and architecture design choices. We successfully quantize models ranging in size from 410M to 52B with minimal degradation in performance.

Arash Ahmadian, Saurabh Dash, Hongyu Chen, Bharat Venkitesh, Stephen Gou, Phil Blunsom, Ahmet Üstün, Sara Hooker
arXiv:2305.19268 · cs.LG, cs.AI · submitted May 30, 2023
abstract · pdf · html · 32 pages, 14 figures

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Also discussed: Jul 2023 (3 points, 2 comments)