In vLLM v0.23.0, `vllm:num_requests_running` is set from `SchedulerStats.num_running_reqs` and observes scheduler running-request state.

MetricvLLM v0.23.0confidence: highverified 10 hr agoverified-code

Why this matters

Useful for questions about what vllm:num_requests_running observes and where its value comes from: the scheduler's running-request count published via SchedulerStats.num_running_reqs.

Metric

num_requests_running

Applies when

V1 scheduler statsPrometheusStatLogger metrics publisher

Evidence

vLLM v0.23.0 v1 metrics stats.py(vllm/v1/metrics/stats.py:171-176)

definesprimarysource_codecode_introspection

vLLM v0.23.0 v1 metrics loggers.py(vllm/v1/metrics/loggers.py:1066-1069)

definesprimarysource_codecode_introspection

Does not establish

queue latency
request success or failure
capacity saturation by itself

Guards

vllm_version = v0.23.0
metric_name = vllm:num_requests_running
runtime_component = scheduler

Freshness

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

In vLLM v0.23.0, vllm:num_requests_running is set from SchedulerStats.num_running_reqs and observes scheduler running-request state.