Puma vs Unicorn

Overview

Unicorn

Stacks479

Followers401

Votes295

GitHub Stars1.5K

Forks269

Puma

Stacks1.2K

Followers265

Votes20

GitHub Stars7.8K

Forks1.5K

Puma vs Unicorn: What are the differences?

Introduction

Puma and Unicorn are both popular web servers used to deploy Ruby applications. While they have similarities in terms of their purpose, they also have key differences that set them apart. In this article, we will explore these differences in detail.

Concurrency Model: One of the main differences between Puma and Unicorn is their concurrency model. Puma utilizes a multi-threaded approach, where each worker process can handle multiple requests concurrently using threads. Unicorn, on the other hand, follows a pre-forking model, where multiple worker processes are created, each with its own memory space, and each worker can handle one request at a time. This difference in concurrency models impacts their performance and resource utilization.
Memory Overhead: Another significant difference between Puma and Unicorn is the memory overhead they introduce. Since Puma utilizes threads, it shares memory amongst the threads, resulting in lower memory overhead compared to Unicorn, which creates separate processes for each worker. This can be advantageous in scenarios where memory efficiency is critical.
Request Timeout Handling: Puma and Unicorn also differ in how they handle request timeouts. Puma provides built-in support for configurable request timeouts, allowing developers to set a maximum time for a request to be processed. Unicorn, on the other hand, does not provide such built-in support and requires additional configuration or middleware to handle request timeouts effectively.
Ease of Configuration: Configuring Puma and Unicorn also differs in terms of complexity. Puma's configuration is more flexible and straightforward, with options to adjust the number of threads and workers easily. Unicorn's configuration, on the other hand, requires specifying the number of worker processes and tuning other parameters to achieve optimal performance. This subtle difference can impact the ease of deployment and maintenance of Ruby applications.
Compatibility with MRI and JRuby: Puma and Unicorn also differ in their compatibility with different Ruby implementations. Puma is designed to work well with both MRI (Matz's Ruby Interpreter) and JRuby, making it a more versatile choice. Unicorn, while primarily developed for MRI, can also work with JRuby, but it may require special considerations and configurations to achieve optimal performance in a JRuby environment.
Support for Streaming Responses: When it comes to handling streaming responses, Puma and Unicorn exhibit differences. Puma has built-in support for streaming responses, allowing developers to progressively send data to clients while the response is being generated. This can be advantageous for use cases such as real-time data updates or video streaming. Unicorn, on the other hand, does not have native support for streaming responses, requiring additional configurations or middleware to handle such scenarios effectively.

In summary, Puma and Unicorn differ in their concurrency models, memory overhead, request timeout handling, ease of configuration, compatibility with different Ruby implementations, and support for streaming responses. These differences make them better suited for different use cases, and understanding these distinctions can guide developers in selecting the optimal web server for their specific application requirements.

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Advice on Unicorn, Puma

Mark

Software Developer at Nouveta

Mar 4, 2022

Needs adviceon

Rails

Ruby

Puma

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.

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Comments

Detailed Comparison

Unicorn	Puma
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.	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.
Statistics
GitHub Stars 1.5K	GitHub Stars 7.8K
GitHub Forks 269	GitHub Forks 1.5K
Stacks 479	Stacks 1.2K
Followers 401	Followers 265
Votes 295	Votes 20
Pros & Cons
Pros 81 Fast 59 Performance 36 Web server 30 Very light 30 Open Source Cons 4 Not multithreaded	Pros 4 Free 3 Convenient 3 Easy 2 Multithreaded 2 First-class support for WebSockets Cons 0 Uses `select` (limited client count)

What are some alternatives to Unicorn, Puma?

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

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

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

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 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 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 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

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.

Caddy

Caddy 2 is a powerful, enterprise-ready, open source web server with automatic HTTPS written in Go.

Related Comparisons

Puma vs Unicorn: What are the differences?

Introduction

Concurrency Model: One of the main differences between Puma and Unicorn is their concurrency model. Puma utilizes a multi-threaded approach, where each worker process can handle multiple requests concurrently using threads. Unicorn, on the other hand, follows a pre-forking model, where multiple worker processes are created, each with its own memory space, and each worker can handle one request at a time. This difference in concurrency models impacts their performance and resource utilization.
Memory Overhead: Another significant difference between Puma and Unicorn is the memory overhead they introduce. Since Puma utilizes threads, it shares memory amongst the threads, resulting in lower memory overhead compared to Unicorn, which creates separate processes for each worker. This can be advantageous in scenarios where memory efficiency is critical.
Request Timeout Handling: Puma and Unicorn also differ in how they handle request timeouts. Puma provides built-in support for configurable request timeouts, allowing developers to set a maximum time for a request to be processed. Unicorn, on the other hand, does not provide such built-in support and requires additional configuration or middleware to handle request timeouts effectively.
Ease of Configuration: Configuring Puma and Unicorn also differs in terms of complexity. Puma's configuration is more flexible and straightforward, with options to adjust the number of threads and workers easily. Unicorn's configuration, on the other hand, requires specifying the number of worker processes and tuning other parameters to achieve optimal performance. This subtle difference can impact the ease of deployment and maintenance of Ruby applications.
Compatibility with MRI and JRuby: Puma and Unicorn also differ in their compatibility with different Ruby implementations. Puma is designed to work well with both MRI (Matz's Ruby Interpreter) and JRuby, making it a more versatile choice. Unicorn, while primarily developed for MRI, can also work with JRuby, but it may require special considerations and configurations to achieve optimal performance in a JRuby environment.
Support for Streaming Responses: When it comes to handling streaming responses, Puma and Unicorn exhibit differences. Puma has built-in support for streaming responses, allowing developers to progressively send data to clients while the response is being generated. This can be advantageous for use cases such as real-time data updates or video streaming. Unicorn, on the other hand, does not have native support for streaming responses, requiring additional configurations or middleware to handle such scenarios effectively.

Puma vs Unicorn

Overview