The statistics of latency measurement: estimands, means and quantiles, histogram aggregation, uncertainty, censoring, dependence, and coordinated omission. Use when an SLO or dashboard reports mean latency, when p99 values are averaged across instances or time windows, when a percentile is quoted without its sample count, when Prometheus buckets are the default set, or when deciding whether two measurements actually differ. Does not cover generating the load (load-testing), sizing systems from throughput (littles-law-and-queueing), or the investigation process itself (performance-methodology). The deep treatment of coordinated omission is coordinated-omission, and tail de…
