Coordination Density: Why the CPU Is Back in the Stack for Agentic AI (opens in new tab)

The CPU never left the stack. It was reclassified — quietly, and incorrectly — as support compute. Something that fed the GPU, scheduled around the GPU, and otherwise stayed out of the way while the GPU did the "real" work. That classification held for exactly as long as AI workloads were big, monolithic training and inference jobs with predictable shapes. It does not hold for agentic systems. In agentic architectures, the CPU is back in the stack as the thing that decides what runs, in what ...