AI inference glossary
Benchmark metrics

GPU utilization

Also known as chip utilization, accelerator utilization

In plain English

GPU utilization measures how busy an accelerator is, though the common percentage from monitoring tools can look high while real efficiency stays low.

Technical definition

GPU utilization is the share of time or capability an accelerator spends doing useful work, reported anywhere from coarse busy percentages to strict measures like model FLOPs utilization.

Engineering details

The utilization number in basic monitoring tools only says a kernel was resident, not that it used the chip well. A kernel occupying one compute unit still reads as busy. Stricter measures compare delivered arithmetic or bandwidth against hardware peaks. In serving, utilization is also shaped by traffic: idle gaps between requests, low concurrency, and tool call pauses in agent sessions all leave paid-for silicon idle.

Why it matters

Fleet economics hinge on utilization. The gap between a well batched, well scheduled deployment and a naive one is often several times the cost per token on identical hardware, which is why serving software and request routing get as much attention as the chips themselves.

How to read it in InferenceX

InferenceX benchmarks report delivered throughput per chip at each interactivity level rather than a utilization percentage, so utilization differences between engines, precisions, and parallelism plans show up directly as separation between curves on the same hardware.