MoM: Linear Sequence Modeling with Mixture-of-Memories
Authors: name: Jusen Du, name: Weigao Sun, name: Disen Lan, name: Jiaxi Hu, name: Yu Cheng

Linear sequence modeling methods, such as linear attention, state space
modeling, and linear RNNs, offer significant efficiency improvements by
reducing the complexity of training and inference. However, these methods
typically compress the entire input sequence into a single fixed-size memory
state, which leads to suboptimal performance on recall-intensive downstream
tasks. Drawing inspiration from neuroscience, particularly the brain's ability
to maintain robust long-term memory while mitigating "memory interference", we
introduce a novel architecture called Mixture-of-Memories (MoM). MoM utilizes
multiple independent memory states, with a router network directing input
tokens to specific memory states. This approach greatly enhances the overall
memory capacity while minimizing memory interference. As a result, MoM performs
exceptionally well on recall-intensive tasks, surpassing existing linear
sequence modeling techniques. Despite incorporating multiple memory states, the
computation of each memory state remains linear in complexity, allowing MoM to
retain the linear-complexity advantage during training, while
constant-complexity during inference. Our experimental results show that MoM
significantly outperforms current linear sequence models on downstream language
tasks, particularly recall-intensive tasks, and even achieves performance
comparable to Transformer models. The code is released at
https://github.com/OpenSparseLLMs/MoM and is also released as a part of
https://github.com/OpenSparseLLMs/Linear-MoE.