The Hallway Track
Engineering Insights

Mixture-of-Experts kernel engineering on Amazon SageMaker AI

AWS Machine Learning Blog · Oct 13, 2026 · Engineering Insights

AWS details kernel-level MoE optimizations on SageMaker targeting Hopper GPU decode-phase bottlenecks

“A fused MoE system merges token routing, data shuffling, and specialized network calculations into a single batched operation on the GPU.”

AWS describes low-level GPU kernel optimizations for Mixture-of-Experts models on SageMaker, focusing on a Swap-AB technique to better utilize NVIDIA Hopper's WGMMA instruction during the decode phase. The core problem is that MoE decode processes one token at a time, leaving Tensor Core capacity underutilized due to a hardware-enforced M=64 minimum dimension constraint. This is useful infrastructure signal for teams running MoE models at scale but is a niche engineering post rather than a broad industry announcement.

mixture-of-experts kernel-optimization aws-sagemaker gpu-inference nvidia-hopper llm-serving

Watch / read the original source →