Augmenting Language Models with Long-Term Memory
Authors: name: Weizhi Wang; name: Li Dong; name: Hao Cheng; name: Xiaodong Liu; name: Xifeng Yan; name: Jianfeng Gao; name: Furu Wei
Published: 2023-06-12 15:13:39

Abstract: Existing large language models (LLMs) can only afford fix-sized inputs due to
the input length limit, preventing them from utilizing rich long-context
information from past inputs. To address this, we propose a framework, Language
Models Augmented with Long-Term Memory (LongMem), which enables LLMs to
memorize long history. We design a novel decoupled network architecture with
the original backbone LLM frozen as a memory encoder and an adaptive residual
side-network as a memory retriever and reader. Such a decoupled memory design
can easily cache and update long-term past contexts for memory retrieval
without suffering from memory staleness. Enhanced with memory-augmented
adaptation training, LongMem can thus memorize long past context and use
long-term memory for language modeling. The proposed memory retrieval module
can handle unlimited-length context in its memory bank to benefit various
downstream tasks. Typically, LongMem can enlarge the long-form memory to 65k
tokens and thus cache many-shot extra demonstration examples as long-form
memory for in-context learning. Experiments show that our method outperforms
strong long-context models on ChapterBreak, a challenging long-context modeling
benchmark, and achieves remarkable improvements on memory-augmented in-context
learning over LLMs. The results demonstrate that the proposed method is
effective in helping language models to memorize and utilize long-form
contents. Our code is open-sourced at https://aka.ms/LongMem.