DictLLM: Dictionary-Based Post-Training Compression for LLMs
DictLLM is a new post-training compression method that decomposes weight matrices into a shared dictionary and layer-specific sparse coefficients, using SVD and Hessian-based sparsification and quantization. It achieves a 5.1x compression of LLaMA-7B with only a 2.9-point perplexity increase on WikiText-2, outperforming existing low-rank methods. The approach requires no further training and is designed for efficient deployment on mobile devices.