arXiv Machine Learning

QK-Wanda: Coupling Queries and Keys for Unstructured Pruning

QK-Wanda is a new pruning method that extends Wanda by scoring query and key weights together, using each projection’s deletion cost under an unmasked pre‑RoPE reconstruction objective. It augments each projection’s score with information from the opposite projection, enabling shared pruning budgets without requiring gradients or weight updates. Across 15 models ranging from 0.5 B to 72 B parameters, QK-Wanda reduces reconstruction error by 60 % at 50 % sparsity and 45 % at 80 % compared to Wanda, and yields notable downstream improvements on some models such as Llama 2 70 B. whyItMatters":"The study demonstrates that coupling query and key pruning criteria can substantially lower reconstruction error and improve downstream performance, highlighting both the potential and limitations of local reconstruction as a predictor of model quality."

arXiv Machine Learning
Aug 24

COEC: Calibrated Orthogonal-Equivalence Compensation for Structured Pruning of Large Language Models

COEC (Calibrated Orthogonal-Equivalence Compensation) is a training‑free framework that improves structured pruning of large language models by applying alternating left and right orthogonal rotations to the retained weight matrix. The method optimizes the right rotation on a reduced Stiefel manifold, rescales singular values via generalized cross‑validation, tempers the calibration Gram matrix, and adds an alignment penalty to preserve geometric relations between attention projections. Experiments on Llama‑3, Llama‑3.1, and Qwen2.5 show that COEC consistently improves perplexity and zero‑shot accuracy across multiple sparsity levels, outperforming existing compensation techniques.

By Peiqi Yu, Nam Ling, Wei Wang, Wei Jiang
arXiv Machine Learning
Sep 25

Task-Aware Spectral Pruning: A Mixture-of-Masks Framework for Efficient LLM Inference

Task-Aware Spectral Pruning (TASP) is a post‑training framework that tailors sparse masks to specific tasks by calibrating module‑level spectral descriptors against task‑specific ablation effects. It constructs masks that close grouped‑query‑attention and SwiGLU dependencies, routing each user turn to a single compiled mask that remains fixed during prefill and decoding. In experiments, TASP achieves a 43% active‑FLOP reduction while preserving 97.7% of the dense BF16 performance on Llama‑3‑70B, and delivers a 1.44× speedup on an A100 80GB with INT8‑weight/BF16‑compute, reducing decode latency from 45.2 to 31.3 ms/token.

By Ibne Farabi Shihab, Fariya Afrin, Sanjeda Akter, Anuj Sharma
arXiv Computation and Language
Aug 31

Pruning Laws for Large Language Models

arXiv:2504.04342v2 Announce Type: replace Abstract: Scaling up model parameters and training data consistently improves the performance of large language models (LLMs), but at the cost of rapidly gro...

By Ayan Sengupta, Siddhant Chaudhary, Tanmoy Chakraborty
arXiv Computation and Language
3d ago

Listening to the Wise Few: Query-Key Alignment Unlocks Latent Correct Answers in Large Language Models

arXiv:2410.02343v2 Announce Type: replace Abstract: Large language models (LLMs) routinely fail to output the correct option in multiple-choice question answering (MCQA) while encoding the answer int...

By Eduard Tulchinskii, Kristian Kuznetsov, Laida Kushnareva, Anastasia Voznyuk, Andrei Andriiainen, Irina Piontkovskaya, Evgeny Burnaev, Serguei Barannikov
arXiv AI
Sep 17

Higher-order pruning of experts in mixture-of-experts language models

The paper introduces HOPE, a second‑order pruning method for Mixture‑of‑Experts language models that accounts for cooperative interactions between experts. Unlike first‑order methods such as REAP, HOPE derives an objective that provably bounds pruning error and is shown to outperform baselines across three large MoE models, multiple calibration sets, and diverse benchmarks, especially at high pruning rates and on agentic tasks. The results demonstrate that preserving expert interactions allows aggressive compression with minimal performance loss on complex workloads.

By Alex M. Tseng, Prannay Kaul, Luca Zancato, Wei Xia, Stefano Soatto
arXiv AI
Jul 7

HiFA4: Training-Free 4-bit FlashAttention on Ascend HIF4 NPUs for LLM Inference

arXiv:2607. 04302v1 Announce Type: cross Abstract: We present HiFA4, a post-training operator-level design that executes both QK^T and PV in FlashAttention as 4-bit HIF4 Cube GEMMs for LLM inference on Ascend NPUs, while maintaining the online softmax state in FP16.

By Hui Dong, Yanzhao Li, Jie Gao, Chunlu Li, Zhiyuan Zhang, Yupeng Sun, Zhenyuan Chen, Zhiqiang Zou