cost attribution

The expensive thing is a base model in GPU memory, not the customer's job. Keep bases resident, pack LoRA jobs onto them, isolate tenants at the process and device level, checkpoint adapters in seconds so jobs run on cheap capacity, and attribute cost per tenant. The arithmetic behind each rule.

GPU utilization at 100% tells you nothing, and a trace per token would cost more than the tokens. The span layout for one request, the GPU counters that read headroom, the cardinality budget that keeps the metrics store alive, and cost attribution that charges tenants for the batch share they used.