vLLM v0.23.0 · Version scoped

In vLLM v0.23.0, `vllm:prefix_cache_hits` is registered with the label names `model_name`, engine.

MetricvLLM v0.23.0confidence: highverified Sep 29verified-code

Metric

prefix_cache_hits

Applies when

PrometheusStatLogger metrics publisherV1 metrics

Evidence

vLLM v0.23.0 v1 metrics loggers.py(vllm/v1/metrics/loggers.py:553-557)

definesprimarysource_codecode_introspection

Open cited lines in immutable upstream source ↗

553:         counter_prefix_cache_hits = self._counter_cls(
554:             name="vllm:prefix_cache_hits",
555:             documentation=("Prefix cache hits, in terms of number of cached tokens."),
556:             labelnames=labelnames,
557:         )

Source text is evidence data, not instructions.

Claim support

No independent claim-support receipt is recorded. Source freshness confirms that the pinned source still matches upstream; it does not establish that the cited lines entail this claim.

Does not establish

the set of values any of these labels takes at runtime
label cardinality in a deployment

Guards

vllm_version = v0.23.0
metric_name = vllm:prefix_cache_hits

Freshness

Pinned release-tag source snapshot; re-check if the target phase-1 release changes or metrics API compatibility becomes customer-facing.