  Low-Rank Adaptation (LoRA) offers an efficient way to fine-tune large
language models (LLMs). Its modular and plug-and-play nature allows the
integration of various domain-specific LoRAs, enhancing LLM capabilities.
Open-source platforms like Huggingface and Modelscope have introduced a new
computational paradigm, Uploadable Machine Learning (UML). In UML, contributors
use decentralized data to train specialized adapters, which are then uploaded
to a central platform to improve LLMs. This platform uses these domain-specific
adapters to handle mixed-task requests requiring personalized service. Previous
research on LoRA composition either focuses on specific tasks or fixes the LoRA
selection during training. However, in UML, the pool of LoRAs is dynamically
updated with new uploads, requiring a generalizable selection mechanism for
unseen LoRAs. Additionally, the mixed-task nature of downstream requests
necessitates personalized services. To address these challenges, we propose
Retrieval-Augmented Mixture of LoRA Experts (RAMoLE), a framework that
adaptively retrieves and composes multiple LoRAs based on input prompts. RAMoLE
has three main components: LoraRetriever for identifying and retrieving
relevant LoRAs, an on-the-fly MoLE mechanism for coordinating the retrieved
LoRAs, and efficient batch inference for handling heterogeneous requests.
Experimental results show that RAMoLE consistently outperforms baselines,
highlighting its effectiveness and scalability.
