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LLM optimizer switching has minimal performance cost, study finds

A new arXiv paper investigates the impact of switching optimizers during large language model (LLM) training. Researchers found that performance is largely determined by the independent effects of the pretraining and post-training optimizers, rather than a significant penalty for mismatch. Specifically, increasing the proportion of updates with the Muon optimizer during supervised fine-tuning (SFT) generally improved downstream performance, even when models were pretrained with AdamW. While matching the pretraining optimizer can reduce forgetting during SFT, it did not lead to better final benchmark results. AI

IMPACT Suggests flexibility in choosing optimizers for post-training stages of LLMs without significant performance degradation.

RANK_REASON Academic paper on LLM training methodology. [lever_c_demoted from research: ic=1 ai=1.0]

Read on arXiv cs.LG →

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LLM optimizer switching has minimal performance cost, study finds

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Academic paper on LLM training methodology. [lever_c_demoted from research: ic=1 ai=1.0]
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COVERAGE [1]

  1. arXiv cs.LG TIER_1 English(EN) · Xinyu Zhao, Davis Wertheimer, Ashutosh Sharma, Rameswar Panda, Paul Pu Liang ·

    The Ephemeral Cost of Switching Optimizers Across LLM Training Stages

    arXiv:2610.22650v1 Announce Type: new Abstract: Recent work suggests that switching optimizers between pretraining and subsequent training stages incurs a performance cost, but systematic investigation of this phenomenon is lacking. We study the mismatch between AdamW and Muon op…