MemoRAG: Moving towards Next-Gen RAG Via Memory-Inspired Knowledge
  Discovery
Authors: name: Hongjin Qian; name: Peitian Zhang; name: Zheng Liu; name: Kelong Mao; name: Zhicheng Dou
Published: 2024-09-09 13:20:31

Abstract: Retrieval-Augmented Generation (RAG) leverages retrieval tools to access
external databases, thereby enhancing the generation quality of large language
models (LLMs) through optimized context. However, the existing retrieval
methods are constrained inherently, as they can only perform relevance matching
between explicitly stated queries and well-formed knowledge, but unable to
handle tasks involving ambiguous information needs or unstructured knowledge.
Consequently, existing RAG systems are primarily effective for straightforward
question-answering tasks. In this work, we propose MemoRAG, a novel
retrieval-augmented generation paradigm empowered by long-term memory. MemoRAG
adopts a dual-system architecture. On the one hand, it employs a light
but long-range LLM to form the global memory of database. Once a task is
presented, it generates draft answers, cluing the retrieval tools to locate
useful information within the database. On the other hand, it leverages an
expensive but expressive LLM, which generates the ultimate answer
based on the retrieved information. Building on this general framework, we
further optimize MemoRAG's performance by enhancing its cluing mechanism and
memorization capacity. In our experiment, MemoRAG achieves superior performance
across a variety of evaluation tasks, including both complex ones where
conventional RAG fails and straightforward ones where RAG is commonly applied.