Fast and Continual Knowledge Graph Embedding via Incremental LoRA
Jiajun Liu, Wenjun Ke, Peng Wang, Jiahao Wang, Jinhua Gao, Ziyu Shang, Guozheng Li, Zijie Xu, Ke Ji, Yining Li
TL;DR
This work tackles continual knowledge graph embedding (CKGE) by addressing both the need to learn new knowledge efficiently and to preserve previously learned information as knowledge graphs grow. It introduces FastKGE, a framework that combines graph layering with Incremental Low-Rank Adapters (IncLoRA) and adaptive rank allocation to store emerging knowledge in layer-specific, low-parameter modules while freezing prior embeddings. The approach yields substantial training-time savings (roughly 34-68% depending on dataset) with competitive link prediction performance across standard CKGE benchmarks and two newly constructed large-scale datasets (FB-CKGE, WN-CKGE). This work demonstrates the practicality of scalable CKGE and provides open datasets and insights for using low-rank adapters to manage continual knowledge growth in graphs.
Abstract
Continual Knowledge Graph Embedding (CKGE) aims to efficiently learn new knowledge and simultaneously preserve old knowledge. Dominant approaches primarily focus on alleviating catastrophic forgetting of old knowledge but neglect efficient learning for the emergence of new knowledge. However, in real-world scenarios, knowledge graphs (KGs) are continuously growing, which brings a significant challenge to fine-tuning KGE models efficiently. To address this issue, we propose a fast CKGE framework (\model), incorporating an incremental low-rank adapter (\mec) mechanism to efficiently acquire new knowledge while preserving old knowledge. Specifically, to mitigate catastrophic forgetting, \model\ isolates and allocates new knowledge to specific layers based on the fine-grained influence between old and new KGs. Subsequently, to accelerate fine-tuning, \model\ devises an efficient \mec\ mechanism, which embeds the specific layers into incremental low-rank adapters with fewer training parameters. Moreover, \mec\ introduces adaptive rank allocation, which makes the LoRA aware of the importance of entities and adjusts its rank scale adaptively. We conduct experiments on four public datasets and two new datasets with a larger initial scale. Experimental results demonstrate that \model\ can reduce training time by 34\%-49\% while still achieving competitive link prediction performance against state-of-the-art models on four public datasets (average MRR score of 21.0\% vs. 21.1\%).Meanwhile, on two newly constructed datasets, \model\ saves 51\%-68\% training time and improves link prediction performance by 1.5\%.
