Hugging Face Blog

How we sped up transformer inference 100x for 🤗 API customers

arXiv AI
Sep 24

KITE: KV-Invariant Transformer Expansion for Efficient Agentic LLM Scaling

KITE (KV-Invariant Transformer Expansion) is a scaling paradigm that trains a language model from a smaller size to a larger one, saving training costs by upcycling. It places new parameters in regions that do not affect attention KV, so inference only requires prefilling KV from the smaller part, reducing inference costs. The Step Scale Transformer (SST), a two-tower decoder, demonstrates this by achieving lower training loss than comparable MoE Transformers while cutting estimated inference cost by 6.7% and 31.6%.

By Zhiheng Hu, Yixun Wei, Jian Zhou, Yizhuang Zhou, Ji Li, Xing Chen, Yang Li, Bojun Wang, Yibo Zhu, Xiangyu Zhang, Daxin Jiang
arXiv Machine Learning
Sep 2

Performance-Efficiency Tradeoffs in Transformers: An Approximation Theory Perspective

The paper examines how to allocate attention heads and head dimensions across Transformer layers to balance expressivity and efficiency. It provides a mathematical analysis of early layers’ role in information extraction and characterizes the trade‑off between head count and dimension under a fixed parameter budget. The authors prove a saturation effect of softmax activations, showing that increasing head dimensions yields diminishing returns, especially for long sequences, and propose strategies for efficient parameter allocation across layers.

By Ruoxi Yu, Haotian Jiang, Jingpu Cheng, Penghao Yu, Qianxiao Li, Zhong Li