# giltene/wrk2

A constant throughput, correct latency recording variant of wrk

Repository: https://github.com/giltene/wrk2
Canonical: https://ross.abutalabs.com/products/wrk2
Language: C
License: Apache-2.0
License Family: permissive
Last push: 2024-03-03T13:40:01+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 4316, "days_push": 913, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4626, forks 425 (observed 2026-08-28T04:08:55.208128+00:00)

## What it is
wrk2 is a constant-throughput HTTP benchmarking tool based on wrk, modified to produce accurate latency recordings using HdrHistograms. It avoids Coordinated Omission by measuring latency from the planned send time, enabling accurate high-percentile (up to 99.9999%) latency reporting.

## Use cases
- load test an HTTP API at a fixed requests-per-second rate
- measure accurate tail latencies like 99.99th percentile for a web service
- benchmark a server without Coordinated Omission skewing results
- compare latency of endpoints under constant throughput load
- script HTTP load tests with Lua request generation

## When to choose
- you need correct high-percentile latency numbers rather than averages
- you want constant-throughput load generation instead of open-loop max load
- you are already familiar with wrk and want more accurate latency recording

## When to avoid
- you need sub-millisecond latency precision (accuracy is limited to ~1 msec granularity)
- you need load testing of non-HTTP protocols
- you want a actively developed tool with frequent updates

## Facets
- artifact type: cli-tool
- maturity: maintenance
- function: benchmarking, http-client, load-testing
- domain: developer-tools, performance, testing, web-development
- platform: cli
- tags: http-benchmarking, hdrhistogram, coordinated-omission, latency-measurement, load-generator, linux, macos

## Member repositories
- giltene/wrk2 (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:55.208128+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 2026-08-29T18:19:38.102928+00:00, confidence not recorded.
  - readme: https://github.com/giltene/wrk2 (fetched 2026-08-28T04:08:55.208128+00:00, sha c953dfacf2e8)
- Data as of 2026-08-30T08:39:29.467469+00:00.