arXiv Machine Learning By Eugene Belilovsky, Stefan Horoi, Edouard Oyallon, Benjamin Th\'erien

How Inner Optimizers Shape Replica Scaling

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The paper investigates how different inner optimizers affect replica scaling when training large language models across distributed compute resources. It identifies two key factors—covariance of pseudo-gradients and batch-size impact on noise scale—that influence performance as replicas increase. The authors show that whitening-based pre‑conditioning as an inner optimizer yields strong replica scaling, improving performance relative to DP as model size and data grow.

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