Which Routing Does Each MoE Model Use? DeepSeek, Qwen, Mixtral, Llama 4, gpt-oss Compared
Open Mixture-of-Experts (MoE) models share one idea but disagree on almost every routing detail. Expert counts range from 8 to 384. Top-k ranges from 1 to 8. Some models keep an always-on shared expert; others drop it. TL;DR Size: 10 models, from Qwen3.6-35B-A3B (35B total, 3B active) to DeepSeek-V4-Pro (1.6T total, 49B active). Runs on: gpt-oss-120b fits one 80 GB GPU with MXFP4; DeepSeek-V4-Pro and Kimi K2 need multi-GPU expert parallelism. Performance: Routed sparsity spans 4x in Mixtral (8 experts, top-2) to 128x in Llama 4 Maverick (128, top-1). Best: Kimi K2 found sparsity 48 needed 1.69x fewer FLOPs than sparsity 8 at equal validation loss. Worst: Llama 4 Maverick and gpt-oss do not publish their gating or balancing method in config.json. Bottom line: Best thing: configs make routing fully auditable. Worst thing: names like “17B active” hide very different routers. How do open MoE models route tokens? Every model below uses...
