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Puma
Puma

255
142
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Unicorn
Unicorn

479
297
+ 1
292
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Puma vs Unicorn: What are the differences?

Puma: A Modern, Concurrent Web Server for Ruby. 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; 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.

Puma and Unicorn can be categorized as "Web Servers" tools.

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

Puma and Unicorn are both open source tools. Puma with 5.78K GitHub stars and 987 forks on GitHub appears to be more popular than Unicorn with 1.35K GitHub stars and 249 GitHub forks.

Instacart, Harvest, and New Relic are some of the popular companies that use Unicorn, whereas Puma is used by Yammer, Product Hunt, and GrowthHackers. Unicorn has a broader approval, being mentioned in 176 company stacks & 55 developers stacks; compared to Puma, which is listed in 73 company stacks and 30 developer stacks.

What is 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.

What is Unicorn?

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.
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What tools integrate with Puma?
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    No integrations found
      No integrations found
      What are some alternatives to Puma and Unicorn?
      Atlas
      Atlas is one foundation to manage and provide visibility to your servers, containers, VMs, configuration management, service discovery, and additional operations services.
      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.
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      Decisions about Puma and Unicorn
      Jerome Dalbert
      Jerome Dalbert
      Senior Backend Engineer at StackShare | 6 upvotes 36K views
      atStackShareStackShare
      Unicorn
      Unicorn
      Puma
      Puma
      Rails
      Rails

      We switched from Unicorn (process model) to Puma (threaded model) to decrease the memory footprint of our Rails production web server. Memory indeed dropped from 6GB to only 1GB!

      We just had to decrease our worker count and increase our thread count instead. Performance (response time and throughput) remained the same, if not slightly better. We had no thread-safety errors, which was good.

      Free bonus points are:

      • Requests are blazing fast on our dev and staging environments!
      • Puma has first-class support for WebSockets, so we know for sure that Rails ActionCable or GraphQL subscriptions will work great.
      • Being on Puma makes us even more "default Rails"-compliant since it is the default Rails web server these days.
      See more
      Simon Bettison
      Simon Bettison
      Managing Director at Bettison.org Limited | 6 upvotes 105.4K views
      atBettison.org LimitedBettison.org Limited
      PostgreSQL
      PostgreSQL
      Elasticsearch
      Elasticsearch
      Sidekiq
      Sidekiq
      Redis
      Redis
      Amazon ElastiCache
      Amazon ElastiCache
      Rails
      Rails
      RSpec
      RSpec
      Selenium
      Selenium
      Travis CI
      Travis CI
      Ruby
      Ruby
      Unicorn
      Unicorn
      nginx
      nginx
      Amazon CloudFront
      Amazon CloudFront
      Amazon SES
      Amazon SES
      Amazon SQS
      Amazon SQS
      Amazon Route 53
      Amazon Route 53
      Amazon VPC
      Amazon VPC
      Docker
      Docker
      Amazon EC2 Container Service
      Amazon EC2 Container Service

      In 2010 we made the very difficult decision to entirely re-engineer our existing monolithic LAMP application from the ground up in order to address some growing concerns about it's long term viability as a platform.

      Full application re-write is almost always never the answer, because of the risks involved. However the situation warranted drastic action as it was clear that the existing product was going to face severe scaling issues. We felt it better address these sooner rather than later and also take the opportunity to improve the international architecture and also to refactor the database in. order that it better matched the changes in core functionality.

      PostgreSQL was chosen for its reputation as being solid ACID compliant database backend, it was available as an offering AWS RDS service which reduced the management overhead of us having to configure it ourselves. In order to reduce read load on the primary database we implemented an Elasticsearch layer for fast and scalable search operations. Synchronisation of these indexes was to be achieved through the use of Sidekiq's Redis based background workers on Amazon ElastiCache. Again the AWS solution here looked to be an easy way to keep our involvement in managing this part of the platform at a minimum. Allowing us to focus on our core business.

      Rails ls was chosen for its ability to quickly get core functionality up and running, its MVC architecture and also its focus on Test Driven Development using RSpec and Selenium with Travis CI providing continual integration. We also liked Ruby for its terse, clean and elegant syntax. Though YMMV on that one!

      Unicorn was chosen for its continual deployment and reputation as a reliable application server, nginx for its reputation as a fast and stable reverse-proxy. We also took advantage of the Amazon CloudFront CDN here to further improve performance by caching static assets globally.

      We tried to strike a balance between having control over management and configuration of our core application with the convenience of being able to leverage AWS hosted services for ancillary functions (Amazon SES , Amazon SQS Amazon Route 53 all hosted securely inside Amazon VPC of course!).

      Whilst there is some compromise here with potential vendor lock in, the tasks being performed by these ancillary services are no particularly specialised which should mitigate this risk. Furthermore we have already containerised the stack in our development using Docker environment, and looking to how best to bring this into production - potentially using Amazon EC2 Container Service

      See more
      Interest over time
      Reviews of Puma and Unicorn
      No reviews found
      How developers use Puma and Unicorn
      Avatar of SmartLogic
      SmartLogic uses UnicornUnicorn

      Rolling deploys are awesome! We use Unicorn to keep downtime to a minimum as we iterate quickly for our clients.

      Avatar of Avalanche Network
      Avalanche Network uses UnicornUnicorn

      Our super server that runs a web instance and a worker instance.

      Avatar of douglasresende
      douglasresende uses UnicornUnicorn

      I use with my Ruby on Rails projects.

      Avatar of Karma
      Karma uses UnicornUnicorn

      Our go-to Ruby application server.

      Avatar of Oded Arbel
      Oded Arbel uses PumaPuma

      Server for Rails-powered API

      Avatar of Satoru Ishikawa
      Satoru Ishikawa uses PumaPuma

      Heroku 銇у嫊銇嬨仚Web銈点兗銉愩兗

      Avatar of Jamie Yun
      Jamie Yun uses PumaPuma

      expert

      How much does Puma cost?
      How much does Unicorn cost?
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