KnowLA: Enhancing Parameter-efficient Finetuning with Knowledgeable Adaptation
Xindi Luo, Zequn Sun, Jing Zhao, Zhe Zhao, Wei Hu
TL;DR
KnowLA addresses the challenge of enhancing parameter-efficient finetuning for large language models by injecting knowledge graph embeddings through a lightweight adaptation layer placed within the decoder stack. It maintains frozen LLM parameters while training a small knowledge adapter that fuses KG information with textual representations during LoRA-based PEFT, enabling the model to activate relevant knowledge without prompting changes. Empirical results across six benchmarks and multiple KG choices show consistent improvements over strong baselines, with notable gains on commonsense and factual reasoning tasks and reduced hallucinations. Analyses reveal that KnowLA aligns KG and LLM semantic spaces and activates latent knowledge in the FFN layers, highlighting a practical path for reliable, knowledge-aware PEFT in large decoder-based LLMs.
Abstract
Parameter-efficient finetuning (PEFT) is a key technique for adapting large language models (LLMs) to downstream tasks. In this paper, we study leveraging knowledge graph embeddings to improve the effectiveness of PEFT. We propose a knowledgeable adaptation method called KnowLA. It inserts an adaptation layer into an LLM to integrate the embeddings of entities appearing in the input text. The adaptation layer is trained in combination with LoRA on instruction data. Experiments on six benchmarks with two popular LLMs and three knowledge graphs demonstrate the effectiveness and robustness of KnowLA. We show that \modelname can help activate the relevant parameterized knowledge in an LLM to answer a question without changing its parameters or input prompts.
