Learning Rate Matters: Vanilla LoRA May Suffice for LLM Fine-tuning

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Lee, Yu-Ang, Ko, Ching-Yun, Chen, Pin-Yu, Yeh, Mi-Yen
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866909054695112704
author Lee, Yu-Ang
Ko, Ching-Yun
Chen, Pin-Yu
Yeh, Mi-Yen
author_facet Lee, Yu-Ang
Ko, Ching-Yun
Chen, Pin-Yu
Yeh, Mi-Yen
contents Low-Rank Adaptation (LoRA) is the prevailing approach for efficient large language model (LLM) fine-tuning. Building on this paradigm, recent studies have proposed alternative initialization strategies, architectural modifications, and optimization adjustments, reporting substantial improvements over vanilla LoRA. However, these gains are often demonstrated under fixed or narrowly tuned hyperparameter settings, despite the known sensitivity of neural networks to training configurations. In this work, we systematically re-evaluate nine representative LoRA variants alongside vanilla LoRA through extensive hyperparameter searches over learning rate, batch size, rank, and training duration. Across tasks spanning mathematical reasoning, commonsense reasoning, code generation, and instruction following at diverse model scales, we find that different LoRA methods favor distinct learning rate ranges. Crucially, once learning rates are properly tuned, all methods achieve similar peak performance (within 1-2%), with only subtle rank-dependent behaviors. These results suggest that vanilla LoRA remains a competitive baseline and that improvements reported under a single training configuration may not reflect consistent methodological advantages. Finally, a second-order analysis attributes the differing optimal learning rate ranges to variations in the largest Hessian eigenvalue, aligning with classical learning theories.
format Preprint
id arxiv_https___arxiv_org_abs_2602_04998
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Learning Rate Matters: Vanilla LoRA May Suffice for LLM Fine-tuning
Lee, Yu-Ang
Ko, Ching-Yun
Chen, Pin-Yu
Yeh, Mi-Yen
Machine Learning
Artificial Intelligence
Computation and Language
Low-Rank Adaptation (LoRA) is the prevailing approach for efficient large language model (LLM) fine-tuning. Building on this paradigm, recent studies have proposed alternative initialization strategies, architectural modifications, and optimization adjustments, reporting substantial improvements over vanilla LoRA. However, these gains are often demonstrated under fixed or narrowly tuned hyperparameter settings, despite the known sensitivity of neural networks to training configurations. In this work, we systematically re-evaluate nine representative LoRA variants alongside vanilla LoRA through extensive hyperparameter searches over learning rate, batch size, rank, and training duration. Across tasks spanning mathematical reasoning, commonsense reasoning, code generation, and instruction following at diverse model scales, we find that different LoRA methods favor distinct learning rate ranges. Crucially, once learning rates are properly tuned, all methods achieve similar peak performance (within 1-2%), with only subtle rank-dependent behaviors. These results suggest that vanilla LoRA remains a competitive baseline and that improvements reported under a single training configuration may not reflect consistent methodological advantages. Finally, a second-order analysis attributes the differing optimal learning rate ranges to variations in the largest Hessian eigenvalue, aligning with classical learning theories.
title Learning Rate Matters: Vanilla LoRA May Suffice for LLM Fine-tuning
topic Machine Learning
Artificial Intelligence
Computation and Language
url https://arxiv.org/abs/2602.04998