MoE

How Mixture of Experts Works: Sparse Gating, Token Routing, and Load Balancing

Large language models face a fundamental scaling trade-off: as parameter counts grow to absorb more world knowledge, the floating-point operations (FLOPs) required per token increase proportionally. In a standard dense Transformer, every single parameter participates in processing every incoming token. Mixture of Experts (MoE) decouples total model capacity from per-token compute cost. By replacing dense feed-forward layers with a dynamic pool of specialized sub-networks ("experts") and routing