Inference Economics: The Real Cost per Token

Deep End Era. Engineering with Sankalp · Oct 10, 2026 · 55m

An inference pilot looks affordable until the invoice arrives. Tokens, memory bandwidth and the growing KV cache explain where the work actually goes, while prefill and decode reveal two different performance problems inside a single request. Batching and serving choices connect utilization to latency. The episode builds a cost-per-token picture and then adds agents, retries and long-tail workloads, asking what an honest operating model must include.

Chapters

00:00:00 Cold open: the invoice that ate the pilot

00:02:21 What a token really is, and why it costs anything

00:04:24 The waiting…