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Unicorn
ByUnicornUnicorn

Unicorn

#43in Platform as a Service
Discussions2
Followers401
OverviewDiscussions2AdoptionAlternativesIntegrations
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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.

Unicorn is a tool in the Platform as a Service category of a tech stack.

Unicorn Pros & Cons

Pros of Unicorn

  • ✓Fast
  • ✓Performance
  • ✓Web server
  • ✓Open Source
  • ✓Very light
  • ✓Rack http server
  • ✓Load balancing
  • ✓Great process management

Cons of Unicorn

  • ✗Not multithreaded

Unicorn Alternatives & Comparisons

What are some alternatives to Unicorn?

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.

Apache Tomcat

Apache Tomcat

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

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.

OpenResty

OpenResty

OpenResty (aka. ngx_openresty) is a full-fledged web application server by bundling the standard Nginx core, lots of 3rd-party Nginx modules, as well as most of their external dependencies.

LiteSpeed

LiteSpeed

It is a drop-in Apache replacement and the leading high-performance, high-scalability server. You can replace your existing Apache server with it without changing your configuration or operating system details. As a drop-in replacement, it allows you to quickly eliminate Apache bottlenecks in 15 minutes with zero downtime.

Try It

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Adoption

On StackShare

Unicorn Discussions

Discover why developers choose Unicorn. Read real-world technical decisions and stack choices from the StackShare community.

Jerome Dalbert
Jerome Dalbert

Principal Backend Software Engineer at StackShare

Mar 17, 2019

Needs adviceonUnicornUnicornPumaPumaRailsRails

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.
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leannematlach
leannematlach

Jun 22, 2015

Needs adviceonUnicornUnicorn

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

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