LZIP-P2P: LOSSLESS COMPRESSION SUPERCHARGED GPU COMMUNICATION

The rapid growth of large language models (LLMs) has made GPU communication a critical bottleneck. While prior work reduces communication volume via quantization or lossy compression, these approaches introduce numerical errors that can degrade convergence, accuracy, and stability. We present LZIP-P2P, a design that integrates lossless compression directly into GPU point-to-point (P2P) communication primitives without compromising numerical correctness. LZIP-P2P employs a split-send pipeline that exposes transmissible data early and overlaps compression with communication, while preserving high GPU efficiency by operating on large data blocks. In real workloads, LZIP-P2P accelerates RL weight synchronization by up to 47.5% without application changes.