Comba: Improving Bilinear RNNs with Closed-loop Control
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Abstract (arXiv)
Recent efficient sequence modeling methods such as Gated DeltaNet, TTT, and RWKV-7 have achieved performance improvements by supervising the recurrent memory management through Delta learning rule. Unlike previous state-space models (e.g., Mamba) and gated linear attentions (e.g., GLA), these models introduce interactions between the recurrent state and the key vector, structurally resembling bilinear systems. In this paper, we first introduce the concept of Bilinear RNNs with a comprehensive analysis on the advantages and limitations of these models. Then, based on closed-loop control theory, we propose a novel Bilinear RNN variant named Comba, which adopts a scalar-plus-low-rank state transition, with both state feedback and output feedback corrections. We also implement a hardware-efficient chunk-wise parallel kernel in Triton and train models with 340M/1.3B parameters on large-scale corpus. Comba demonstrates superior performance and computation efficiency in both language and vision modeling.
Key facts. Cited by 12 papers in the map (data through 7 Oct 2026). Builds on 80 of its 116 references that are in the map. First posted on arXiv 3 Jun 2025.
Builds on
80 of 116 references.
References · 80
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38 more
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- 2024Transformers are SSMs: Generalized Models and Efficient Algorithms Through Structured State Space Dualitycited by 1,283
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50 most cited of 80 All 80 (JSON)
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Citing papers per year: 2025: 1; 2026: 11.
12 papers.
- 2026Mamba-3: Improved Sequence Modeling using State Space Principlescited by 76
- 2025Selective Rotary Position Embeddingcited by 8
- 2026Mem3R: Streaming 3D Reconstruction with Hybrid Memory via Test-Time Trainingcited by 5
- 2026Preconditioned DeltaNet: Curvature-aware Sequence Modeling for Linear Recurrencescited by 5
- 2026Morphing into Hybrid Attention Modelscited by 2
- 2026Memory for Large Language Modelscited by 2
- 2026WriteSAE: Sparse Autoencoders for Recurrent Statecited by 1
- 2026Multi-Mixer Models: Flexible Sequence Modeling with Shared Representationscited by 1
- 2026Proteus: Incremental Memory Activation for Long-Context Sequence Modelingcited by 1
- 2026Kalman Delta Networks: Uncertainty-aware Associative Memorycited by 1
- 2026DREAMSTATE: Diffusing States and Parameters for Recurrent Large Language Modelscited by 0
- 2026Q-Delta: Beyond Key-Value Associative State Evolutioncited by 0
- 2026Kalman Delta Networks: Uncertainty-aware Associative Memory7 Sep 2026
- 2026Proteus: Incremental Memory Activation for Long-Context Sequence Modeling17 Aug 2026
- 2026Memory for Large Language Models28 Jul 2026
- 2026Morphing into Hybrid Attention Models29 Jun 2026
- 2026Q-Delta: Beyond Key-Value Associative State Evolution7 Jun 2026
- 2026Multi-Mixer Models: Flexible Sequence Modeling with Shared Representations27 May 2026
- 2026WriteSAE: Sparse Autoencoders for Recurrent State12 May 2026
- 2026Preconditioned DeltaNet: Curvature-aware Sequence Modeling for Linear Recurrences22 Apr 2026
- 2026Mem3R: Streaming 3D Reconstruction with Hybrid Memory via Test-Time Training8 Apr 2026
- 2026Mamba-3: Improved Sequence Modeling using State Space Principles16 Mar 2026
- 2026DREAMSTATE: Diffusing States and Parameters for Recurrent Large Language Models27 Jan 2026
- 2025Selective Rotary Position Embedding21 Nov 2025
Similar, not cited
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- 2026Improving the Performance and Learning Stability of Parallelizable RNNs Designed for Ultra-Low Power Applications
- 2023Resurrecting Recurrent Neural Networks for Long Sequences
- 2025ParaRNN: Unlocking Parallel Training of Nonlinear RNNs for Large Language Models
- 2026M2RNN: Non-Linear RNNs with Matrix-Valued States for Scalable Language Modeling
- 2025Advancing Intelligent Sequence Modeling: Evolution, Trade-offs, and Applications of State-Space Architectures from S4 to Mamba
- 2024Recurrent neural networks: vanishing and exploding gradients are not the end of the story
- 2025MesaNet: Sequence Modeling by Locally Optimal Test-Time Training
- 2023State space models can express n-gram languages