Struct Histogram 

pub struct Histogram { /* private fields */ }

A fixed-bucket histogram with thread-sharded counters.

Buckets are defined by upper bounds (inclusive). Values are placed in the first bucket whose bound is >= the value. Values exceeding all bounds go in the final “+Inf” bucket.

Implementations

impl Histogram

pub fn new(bounds: &[u64], shard_count: usize) -> Self

Create a histogram with the given bucket boundaries.

Boundaries should be sorted ascending. Each boundary represents the upper bound (inclusive) of a bucket. An implicit +Inf bucket is added.

shard_count is passed to each underlying Counter.

pub fn with_latency_buckets(shard_count: usize) -> Self

Create a histogram with default latency buckets (in microseconds).

Buckets: 10µs, 50µs, 100µs, 500µs, 1ms, 5ms, 10ms, 50ms, 100ms, 500ms, 1s, 5s, 10s

pub fn record(&self, value: u64)

Record a value in the histogram.

pub fn buckets_cumulative(&self) -> Vec<(u64, u64)>

Get cumulative bucket counts – for Prometheus exposition.

Returns pairs of (upper_bound, cumulative_count). The last entry has bound u64::MAX representing +Inf.

Prefer Self::buckets_cumulative_iter on the export path; it avoids the Vec allocation per call.

pub fn buckets_cumulative_iter(&self) -> impl Iterator<Item = (u64, u64)> + '_

Iterator form of Self::buckets_cumulative that skips the Vec allocation. Used by the Prometheus and OTLP export paths.

pub fn sum(&self) -> u64

pub fn count(&self) -> u64

Trait Implementations

impl ClickHouseExport for Histogram

fn export_clickhouse( &self, batch: &mut ClickHouseMetricBatch, name: &str, description: &str, time_unix_nano: u64, )

impl DogStatsDExport for Histogram

fn export_dogstatsd( &self, output: &mut String, name: &str, tags: &[(&str, &str)], )

Export histogram as count + sum metrics.

DogStatsD distributions expect raw samples, not pre-aggregated buckets. We export name.count and name.sum as counters instead.

impl HistogramSnapshot for Histogram

fn count(&self) -> u64

fn sum(&self) -> u64

fn visit_buckets(&self, visitor: &mut dyn FnMut(u64, u64))

impl OtlpExport for Histogram

fn export_otlp( &self, metrics: &mut Vec<Metric>, name: &str, description: &str, time_unix_nano: u64, )

impl PrometheusExport for Histogram

fn export_prometheus(&self, output: &mut String, name: &str, help: &str)

Export this metric to the output string.