arXiv Computation and Language

Sparse Token Routing in Efficient Transformers

The paper introduces Sparse Token Routing in Efficient Transformers, evaluating a two-stream Transformer (SEWN) that routes tokens through either lightweight or full-capacity processing via a learned gate. Experiments show that routing causes negligible accuracy change compared to parameter-matched baselines, and that the effectiveness of the gate’s token-importance signal depends on its learning method. A static lexicon-seeded prior fails a counterfactual faithfulness test on BoolQ, whereas a fully contextual gate achieves highly significant separation ($p<10^{-10}$) on both evaluated tasks without altering task accuracy.

arXiv AI
Jul 2

The State-Prediction Separation Hypothesis

arXiv:2607. 01218v1 Announce Type: cross Abstract: Transformers use the same forward computation stream to both predict the next token and store useful state for future token predictions.

By Giovanni Monea, Nathan Godey, Kiant\'e Brantley, Yoav Artzi
arXiv AI
Aug 11

Full-bandwidth transformer

arXiv:2608. 08888v1 Announce Type: new Abstract: Autoregressive transformers compute along two axes: horizontally across generated tokens, and vertically through model depth.

By Xi Wang, Ziyang Cai, Zheng Zhan, Harry Dong, Ying Fan, Gustavo de Rosa, Tim Pearce, John Langford
arXiv AI
6d ago

T-LoopFormer: Token-Level Elastic-Depth Looped Transformers for Latent Reasoning with Dynamic Routing

T-LoopFormer introduces token-level elastic-depth looped transformers that allow each token to decide its own number of loop iterations based on its hidden state, improving token generation accuracy. It also adds a recursion-wise key‑value cache so tokens at different depths only attend to their corresponding cached states, speeding up autoregressive decoding. Experiments demonstrate strong performance on language modeling and zero‑shot reasoning, achieving the lowest decoding latency among comparable models.

By Mingqian Yu, Wenpeng Zhang, Shaobo Cui, Peilin Zhao
arXiv AI
2d ago

TopK-Guided: Adaptive, Budget-Aware Activation Sparsity for Efficient LLM Inference

TopK-Guided is a training‑free method that improves activation sparsity for large language model inference by combining token‑level sparsity adaptation with block‑level budget allocation that accounts for block sensitivity. It addresses limitations of existing methods like TEAL, which adapts sparsity per token but lacks tight control, and WINA, which enforces a fixed sparsity across all tokens and blocks. Experiments on Llama‑2 and Llama‑3 show that TopK‑Guided consistently yields better perplexity and downstream accuracy while maintaining similar compute costs to WINA, especially at high sparsity levels.

By Mukund Agarwalla, Chih-Jen Lin