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    moonquantilekit

    Streaming quantile and latency summary primitives for MoonBit.

    quantile
    latency
    summary
    streaming
    monitoring
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    Author
    Version
    0.2.0
    License
    Apache-2.0
    Repository
    Last updated
    3 months ago
    Downloads
    48

    No dependencies

    #MoonQuantileKit

    MoonQuantileKit is a MoonBit foundation library for streaming quantile estimation and latency summary evaluation. It focuses on small, deterministic building blocks that can be embedded into benchmarks, service monitors, CLI tools, and reliability reports.

    The initial implementation provides exact and bounded primitives first:

    • sorted sample summaries for P50, P90, P95, P99, and custom percentiles
    • latency bucket histograms for coarse-grained service dashboards
    • snapshot reports with min, max, count, and percentile values
    • JSON export helpers for CI logs and monitoring integrations
    • a CLI demo and regression tests

    #Example

    ///|
    let summary = SampleSummary::new("checkout").add(12).add(35).add(80)

    ///|
    let p95 = summary.percentile(9500)

    The public API uses integer milliseconds and basis-point percentiles to avoid floating-point drift in tests and CI gates.

    BoundedSummary

    source
    pub(all) struct BoundedSummary {
      name : String
      config : SummaryConfig
      centroids : Array[QuantileCentroid]
      sample_count : Int
    } derive(Eq, 
    Debug    )

    BoundedSummary::add

    source
    fn BoundedSummary::add(self : BoundedSummary, value_ms : Int) -> BoundedSummary

    BoundedSummary::capacity

    source
    fn BoundedSummary::capacity(self : BoundedSummary) -> Int

    BoundedSummary::count

    source
    fn BoundedSummary::count(self : BoundedSummary) -> Int

    BoundedSummary::merge

    source

    BoundedSummary::new

    source
    fn BoundedSummary::new(name : String, config : SummaryConfig) -> BoundedSummary

    BoundedSummary::p95

    source
    fn BoundedSummary::p95(self : BoundedSummary) -> Int

    BoundedSummary::percentile

    source
    fn BoundedSummary::percentile(self : BoundedSummary, percentile_bp : Int) -> Int

    BoundedSummary::stored_centroids

    source
    fn BoundedSummary::stored_centroids(self : BoundedSummary) -> Int

    LatencyBucket

    source
    pub(all) struct LatencyBucket {
      upper_ms : Int
      count : Int
    } derive(Eq, 
    Debug    )

    LatencyBucket::new

    source
    fn LatencyBucket::new(upper_ms : Int) -> LatencyBucket

    LatencyBucket::to_json

    source
    fn LatencyBucket::to_json(self : LatencyBucket) -> String

    QuantileCentroid

    source
    pub(all) struct QuantileCentroid {
      mean_ms : Int
      count : Int
    } derive(Eq, 
    Debug    )

    QuantileSnapshot

    source
    pub(all) struct QuantileSnapshot {
      name : String
      count : Int
      min_ms : Int
      max_ms : Int
      p50_ms : Int
      p90_ms : Int
      p95_ms : Int
      p99_ms : Int
    } derive(Eq, 
    Debug    )

    QuantileSnapshot::empty

    source
    fn QuantileSnapshot::empty(self : QuantileSnapshot) -> Bool

    QuantileSnapshot::to_json

    source
    fn QuantileSnapshot::to_json(self : QuantileSnapshot) -> String

    SampleSummary

    source
    pub(all) struct SampleSummary {
      name : String
      values : Array[Int]
    } derive(Eq, 
    Debug    )

    SampleSummary::add

    source
    fn SampleSummary::add(self : SampleSummary, value : Int) -> SampleSummary

    SampleSummary::buckets

    source
    fn SampleSummary::buckets(self : SampleSummary, boundaries_ms : Array[Int]) -> Array[LatencyBucket]

    SampleSummary::count

    source
    fn SampleSummary::count(self : SampleSummary) -> Int

    SampleSummary::from_array

    source
    fn SampleSummary::from_array(name : String, samples : Array[Int]) -> SampleSummary

    SampleSummary::is_empty

    source
    fn SampleSummary::is_empty(self : SampleSummary) -> Bool

    SampleSummary::max

    source
    fn SampleSummary::max(self : SampleSummary) -> Int

    SampleSummary::min

    source
    fn SampleSummary::min(self : SampleSummary) -> Int

    SampleSummary::new

    source
    fn SampleSummary::new(name : String) -> SampleSummary

    SampleSummary::p50

    source
    fn SampleSummary::p50(self : SampleSummary) -> Int

    SampleSummary::p90

    source
    fn SampleSummary::p90(self : SampleSummary) -> Int

    SampleSummary::p95

    source
    fn SampleSummary::p95(self : SampleSummary) -> Int

    SampleSummary::p99

    source
    fn SampleSummary::p99(self : SampleSummary) -> Int

    SampleSummary::percentile

    source
    fn SampleSummary::percentile(self : SampleSummary, percentile_bp : Int) -> Int

    SampleSummary::snapshot

    source

    SummaryConfig

    source
    pub(all) struct SummaryConfig {
      max_samples : Int
      tolerated_error_bp : Int
    } derive(Eq, 
    Debug    )

    SummaryConfig::default

    source
    fn SummaryConfig::default() -> SummaryConfig

    SummaryConfig::exact

    source

    SummaryConfig::is_exact

    source
    fn SummaryConfig::is_exact(self : SummaryConfig) -> Bool

    SummaryConfig::new

    source
    fn SummaryConfig::new(max_samples : Int, tolerated_error_bp : Int) -> SummaryConfig

    SummaryConfig::target_centroids

    source
    fn SummaryConfig::target_centroids(self : SummaryConfig) -> Int

    bucketize

    source
    fn bucketize(samples : Array[Int], boundaries_ms : Array[Int]) -> Array[LatencyBucket]

    clamp_percentile_bp

    source
    fn clamp_percentile_bp(value : Int) -> Int

    Source Files

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