Accelerating Mixture of Experts Training With Rail Optimized InfiniBand Networking in Crusoe Cloud
Feb 12, 2025 · 17:45
Ievgen Bakulenko, product manager at Crusoe Cloud, explains how their rail-optimized InfiniBand networking accelerates training for sparse mixture of experts models. By leveraging NVIDIA's PXN feature, which allows GPUs to communicate across different rails using the internal NVSwitch in a single hop, Crusoe achieves a 50% improvement in synthetic benchmark latency and bandwidth for both small and large messages. In a real-world test fine-tuning the Mixtral model (8 feed-forward blocks, 7 billion parameters) on 240 H100 GPUs, this topology reduced training time by 14%, directly lowering cost and time-to-train. Bakulenko also outlines Crusoe's AI cloud platform, its climate-aligned mission using stranded energy, and its focus on easy-to-use infrastructure for AI engineers.