Towards efficient language giants: A comprehensive survey on structural optimizations and compression techniques for large language models.

The impressive success of large language models (LLMs) across a broad spectrum of NLP tasks has attracted considerable attention in both academia and industry. However, their inference incurs substantial computational and memory overhead, making it challenging to efficiently deploy them in latency-sensitive or resource-constrained environments. This survey provides a comprehensive overview of model-level optimization techniques developed to address these issues. Specifically, we examine efficient module designs for core Transformer components-including multi-head attention, feed-forward networks, normalization, and positional encoding-and summarize representative compression methods such as quantization, pruning, knowledge distillation, approximation, and parameter sharing. We categorize recent advances in each area, analyzing their algorithmic principles, empirical trade-offs, and impact on inference efficiency. Furthermore, we propose practical design strategies that effectively combine efficient modules with compression techniques to significantly reduce inference costs while meeting application-specific accuracy and latency requirements.