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  1. Stackups
  2. Application & Data
  3. Platform as a Service
  4. Web Servers
  5. Cowboy vs Unicorn

Cowboy vs Unicorn

OverviewDecisionsComparisonAlternatives

Overview

Unicorn
Unicorn
Stacks479
Followers401
Votes295
GitHub Stars1.5K
Forks269
Cowboy
Cowboy
Stacks711
Followers72
Votes19
GitHub Stars7.4K
Forks1.2K

Cowboy vs Unicorn: What are the differences?

What is Cowboy? Small, fast, modular HTTP server written in Erlang. Cowboy aims to provide a complete HTTP stack in a small code base. It is optimized for low latency and low memory usage, in part because it uses binary strings. Cowboy provides routing capabilities, selectively dispatching requests to handlers written in Erlang.

What is Unicorn? Rack HTTP server for fast clients and Unix. Unicorn is an HTTP server for Rack applications designed to only serve fast clients on low-latency, high-bandwidth connections and take advantage of features in Unix/Unix-like kernels. Slow clients should only be served by placing a reverse proxy capable of fully buffering both the the request and response in between Unicorn and slow clients.

Cowboy and Unicorn can be primarily classified as "Web Servers" tools.

"Websockets integration" is the primary reason why developers consider Cowboy over the competitors, whereas "Fast" was stated as the key factor in picking Unicorn.

Cowboy and Unicorn are both open source tools. Cowboy with 5.59K GitHub stars and 999 forks on GitHub appears to be more popular than Unicorn with 1.35K GitHub stars and 249 GitHub forks.

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Advice on Unicorn, Cowboy

Mark
Mark

Software Developer at Nouveta

Mar 4, 2022

Needs adviceonRailsRailsRubyRubyPumaPuma

I have an integration service that pulls data from third party systems saves it and returns it to the user of the service. We can pull large data sets with the service and response JSON can go up to 5MB with gzip compression. I currently use Rails 6 and Ruby 2.7.2 and Puma web server. Slow clients tend to prevent other users from accessing the system. Am considering a switch to Unicorn.

38.5k views38.5k
Comments

Detailed Comparison

Unicorn
Unicorn
Cowboy
Cowboy

Unicorn is an HTTP server for Rack applications designed to only serve fast clients on low-latency, high-bandwidth connections and take advantage of features in Unix/Unix-like kernels. Slow clients should only be served by placing a reverse proxy capable of fully buffering both the the request and response in between Unicorn and slow clients.

Cowboy aims to provide a complete HTTP stack in a small code base. It is optimized for low latency and low memory usage, in part because it uses binary strings. Cowboy provides routing capabilities, selectively dispatching requests to handlers written in Erlang.

Statistics
GitHub Stars
1.5K
GitHub Stars
7.4K
GitHub Forks
269
GitHub Forks
1.2K
Stacks
479
Stacks
711
Followers
401
Followers
72
Votes
295
Votes
19
Pros & Cons
Pros
  • 81
    Fast
  • 59
    Performance
  • 36
    Web server
  • 30
    Open Source
  • 30
    Very light
Cons
  • 4
    Not multithreaded
Pros
  • 8
    Websockets integration
  • 6
    Cool name
  • 3
    Good to use with Erlang
  • 2
    Anime mascot

What are some alternatives to Unicorn, Cowboy?

NGINX

NGINX

nginx [engine x] is an HTTP and reverse proxy server, as well as a mail proxy server, written by Igor Sysoev. According to Netcraft nginx served or proxied 30.46% of the top million busiest sites in Jan 2018.

Apache HTTP Server

Apache HTTP Server

The Apache HTTP Server is a powerful and flexible HTTP/1.1 compliant web server. Originally designed as a replacement for the NCSA HTTP Server, it has grown to be the most popular web server on the Internet.

Microsoft IIS

Microsoft IIS

Internet Information Services (IIS) for Windows Server is a flexible, secure and manageable Web server for hosting anything on the Web. From media streaming to web applications, IIS's scalable and open architecture is ready to handle the most demanding tasks.

Apache Tomcat

Apache Tomcat

Apache Tomcat powers numerous large-scale, mission-critical web applications across a diverse range of industries and organizations.

Passenger

Passenger

Phusion Passenger is a web server and application server, designed to be fast, robust and lightweight. It takes a lot of complexity out of deploying web apps, adds powerful enterprise-grade features that are useful in production, and makes administration much easier and less complex.

Gunicorn

Gunicorn

Gunicorn is a pre-fork worker model ported from Ruby's Unicorn project. The Gunicorn server is broadly compatible with various web frameworks, simply implemented, light on server resources, and fairly speedy.

Jetty

Jetty

Jetty is used in a wide variety of projects and products, both in development and production. Jetty can be easily embedded in devices, tools, frameworks, application servers, and clusters. See the Jetty Powered page for more uses of Jetty.

lighttpd

lighttpd

lighttpd has a very low memory footprint compared to other webservers and takes care of cpu-load. Its advanced feature-set (FastCGI, CGI, Auth, Output-Compression, URL-Rewriting and many more) make lighttpd the perfect webserver-software for every server that suffers load problems.

Swoole

Swoole

It is an open source high-performance network framework using an event-driven, asynchronous, non-blocking I/O model which makes it scalable and efficient.

Puma

Puma

Unlike other Ruby Webservers, Puma was built for speed and parallelism. Puma is a small library that provides a very fast and concurrent HTTP 1.1 server for Ruby web applications.

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