HackerReposA FIELD GUIDE TO OPEN SOURCE
ProSponsor the shelf♧ 0
← Back to top all-time
wg
wrk
C2012–2024
wg / wrk

wrk

Modern HTTP benchmarking tool

34Distinct people
42Mentions
3Explicit recommenders
40.4KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Modern HTTP benchmarking tool

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

We use locust at work but I HIGHLY recommend wrk for a very robust yet simple load testing tool. https://github.com/wg/wrk And of course, this talk by Gil Tene is fantastic if…

leetrout used a recommendation phrase. 3 indexed comments match. This is a phrase match, not a verdict.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

Mentioned in the same Hacker News threads. That is not proof they are substitutes.

This week on Hacker News

Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 9:01:12 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year42 dated mentions

Observed mentions: 2012-04-03 22:57:01 UTC to 2024-09-15 08:00:52 UTC.

0369122012-01-01 00:00:00 UTC to 2013-01-01 00:00:00 UTC (exclusive): 2 mentions; 1 submissions, 1 comments20122013-01-01 00:00:00 UTC to 2014-01-01 00:00:00 UTC (exclusive): 12 mentions; 2 submissions, 10 comments2014-01-01 00:00:00 UTC to 2015-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2015-01-01 00:00:00 UTC to 2016-01-01 00:00:00 UTC (exclusive): 4 mentions; 0 submissions, 4 comments2016-01-01 00:00:00 UTC to 2017-01-01 00:00:00 UTC (exclusive): 4 mentions; 0 submissions, 4 comments2017-01-01 00:00:00 UTC to 2018-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments20182019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 3 mentions; 1 submissions, 2 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 4 mentions; 0 submissions, 4 comments2022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 2 mentions; 1 submissions, 1 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 3 mentions; 0 submissions, 3 comments2024

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20122012-01-01 00:00:00 UTC2013-01-01 00:00:00 UTC211
20132013-01-01 00:00:00 UTC2014-01-01 00:00:00 UTC12210
20142014-01-01 00:00:00 UTC2015-01-01 00:00:00 UTC101
20152015-01-01 00:00:00 UTC2016-01-01 00:00:00 UTC404
20162016-01-01 00:00:00 UTC2017-01-01 00:00:00 UTC404
20172017-01-01 00:00:00 UTC2018-01-01 00:00:00 UTC101
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC202
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC202
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC312
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC404
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC211
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC202
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC303

From the project README

An excerpt from the repository, fetched Nov 13, 2026.

Read the project’s introduction
wrk - a HTTP benchmarking tool wrk is a modern HTTP benchmarking tool capable of generating significant load when run on a single multi-core CPU. It combines a multithreaded design with scalable event notification systems such as epoll and kqueue. An optional LuaJIT script can perform HTTP request generation, response processing, and custom reporting. Details are available in SCRIPTING and several examples are located in scripts/. Basic Usage wrk -t12 -c400 -d30s http://127.0.0.1:8080/index.html This runs a benchmark for 30 seconds, using 12 threads, and keeping 400 HTTP connections open. Output: Running 30s test @ http://127.0.0.1:8080/index.html 12 threads and 400 connections Thread Stats Avg Stdev Max +/- Stdev Latency 635.91us 0.89ms 12.92ms 93.69% Req/Sec 56.20k 8.07k 62.00k 86.54% 22464657 requests in 30.00s, 17.76GB read Requests/sec: 748868.53 Transfer/sec: 606.33MB Command Line Options -c, --connections: total number of HTTP connections to keep open with each thread handling N = connections/threads -d, --duration: duration of the test, e.g. 2s, 2m, 2h -t, --threads: total number of threads to use -s, --script: LuaJIT script, see SCRIPTING -H, --header: HTTP header to add to request, e.g. "User-Agent: wrk" --latency: print detailed latency statistics --timeout: record a timeout if a response is not received within this amount of time. Benchmarking Tips The machine running wrk must have a sufficient number of ephemeral ports available and closed sockets should be recycled quickly. To handle the initial connection burst the server's listen(2) backlog should be greater than the number of concurrent connections being tested. A user script that only changes the HTTP method, path, adds headers or a body, will have no performance impact. Per-request actions, particularly building a new HTTP request, and use of response() will necessarily reduce the amount of load that can be generated. Acknowledgements wrk contains code from a number of open source projects including the 'ae' event loop from redis, the nginx/joyent/node.js 'http-parser', and Mike Pall's LuaJIT. Please consult the NOTICE file for licensing details. Cryptography Notice This distribution includes cryptographic software. The country in which you currently reside may have restrictions on the import, possession, use, and/or re-export to another country, of encryption software. BEFORE using any encryption software, please check your country's laws, regulations and policies concerning the import, possession, or use, and re-export of encryption software, to see if this is permitted. See http://www.wassenaar.org/ for more information. The U.S. Government Department of Commerce, Bureau of Industry and Security (BIS), has classified this software as Export Commodity Control Number (ECCN) 5D002.C.1, which includes information security software using or performing cryptographic functions with symmetric algorithms. The form and manner of this distribution makes it eligible for export under the License Exception ENC Technology Software Unrestricted (TSU) exception (see the BIS Export Administration Regulations, Section 740.13) for both object code and source code.
Read the full README on GitHub

What Hacker News says

4 sources
I am under the impression that it's possible to compile Wrk for Windows [1], although I have not personally done so. Incidentally, I've not read the linked article, but skimmed the first few paragraphs. The numbers of requests per second that he was able to generate with various tools seem remarkably low. ApacheBench is the least performant load generator since it's only single-threaded, but it can generate tens of thousands (about 25,000) requests per second on a i7 desktop machine. Wrk can generate significantly more since it uses all CPU cores of the load-generation machine. [1] https://github.com/wg/wrk/issues/49
In How to Generate Millions of HTTP Requests (2012)
The main benefit is this allows rough comparison to a ton of other frameworks. Just running ab against your one server setup gives you one RPS/latency result on one hardware setup - that's good to know as an absolute metric, but tells you very little about your performance relative to other frameworks. This project gives you RPS/latency metrics for many frameworks, on a few hardware setups. This enables a rough comparison of "how does my framework perform relative to all these other well-known or established frameworks". Naturally, the comparison is not perfect - there are a ton of reasons that measuring just requests/sec and latency doesn't allow complete comparison between two frameworks. However, once you accept that it is basically impossible to fully compare any two frameworks using just quantitative methods and these numbers should
Read the rest
inform your choice of framework (instead of totally control your choice of framework), we can talk about why it's valuable. Want to run a low-cost server in language X that you happen to love? This project can provide guidance about which frameworks written in language X are performing the best. Want to ensure your service can support 50k requests per second without loosing latency? This project can provide latency numbers for you to examine that let you know which frameworks appear to maintain acceptable latency even under high load. If you wanted to, you could re-create this project by running ab against 100+ frameworks - that's the cornerstone of what is happening here. Granted, we currently use https://github.com/wg/wrk instead of ab, but the principle is the same - start up framework, run load generation, capture result data. Most of the codebase is dedicated to ensuring that these 100+ frameworks don't interfere with each other, setting up pseudo-production environments with separate server/database/load generation servers, and other concerns that have to be addressed. Over time, this project has started collect more statistics than just requests/second and latency, which makes it more valuable than just running ab. As more metrics are added and more frameworks are added, this becomes a really valuable project for understanding how frameworks perform relative to one another.
In Techempower Web Framework Benchmarks Round 10

MAKE YOURSELF AT HOME

A few shortcuts

/
Search the collection
?
Open this guide
Esc
Close dialogs and navigation

Your saved repositories and interests stay in this browser.