SGLang: a preemption metric under vLLM's name - VERIFIED ABSENT

VERIFIED NEGATIVE. SGLang does not emit a preemption metric under vLLM's name. sglang:num_preemptions is NOT a metric this engine registers - it is recorded here under the conventional name a reader would go looking for so the absence is queryable rather than implied by a gap in a list. SGLang's preemption concept is RETRACTION and it measures it more finely than vLLM does - an instantaneous gauge plus three cumulative counters including an input/output token split. The capability is present; only the vLLM name is absent. What was searched: grep for name="sglang:num_preemptions" returns zero hits; grep for 'retract' in the collector returns the num_retracted_* family.. Do not read this record's metric_name as something the engine exports; it is the name that is missing.