# HdrHistogram/HdrHistogram

A High Dynamic Range (HDR) Histogram

Repository: https://github.com/HdrHistogram/HdrHistogram
Canonical: https://ross.abutalabs.com/products/hdrhistogram
Homepage: http://hdrhistogram.github.io/HdrHistogram/
Language: Java
License: NOASSERTION
License Family: other
Last push: 2024-06-27T13:01:32+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 5105, "days_push": 797, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2316, forks 272 (observed 2026-08-28T04:06:36.819210+00:00)

## What it is
HdrHistogram is a Java library for recording and analyzing sampled data value counts across a configurable integer value range with configurable precision, designed for latency and performance measurement. It supports high dynamic range histograms with low, controlled quantization error, with ports available in many other languages.

## Use cases
- measure latency percentiles in performance-sensitive applications
- record response time distributions from microseconds to hours
- analyze benchmark results with high dynamic range histograms
- track value counts with configurable significant-digit precision
- generate percentile spectrum plots of latency data

## When to choose
- you need accurate latency percentile tracking (p50, p99, p99.9) in Java/JVM applications
- you need to record measurements spanning many orders of magnitude with bounded quantization error
- you are building benchmarking or performance monitoring tooling

## When to avoid
- you need simple averages or sums rather than distribution analysis
- you need a general-purpose time-series metrics storage system
- your platform is not among the available language ports and you cannot use Java

## Facets
- artifact type: library
- maturity: stable
- function: benchmarking, monitoring, analytics
- domain: performance, developer-tools, analytics
- platform: jvm, cross-platform
- tags: histogram, latency-measurement, percentiles, hdr, metrics

## Member repositories
- HdrHistogram/HdrHistogram (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:36.819210+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:38:57.372313+00:00, confidence not recorded.
  - readme: https://github.com/HdrHistogram/HdrHistogram (fetched 2026-08-28T04:06:36.819210+00:00, sha b1a617316acd)
  - homepage: http://hdrhistogram.github.io/HdrHistogram/ (fetched 2026-08-29T10:19:13.633049+00:00, sha 0a2c8dd488bf)
- Data as of 2026-08-30T08:39:29.467469+00:00.