Software Alternatives, Accelerators & Startups

Apache Tomcat VS Unicorn

Compare Apache Tomcat VS Unicorn and see what are their differences

Apache Tomcat logo Apache Tomcat

An open source software implementation of the Java Servlet and JavaServer Pages technologies

Unicorn logo Unicorn

Unicorn is an HTTP server for Rack applications designed to only serve fast clients on low-latency, high-bandwidth connections.
  • Apache Tomcat Landing page
    Landing page //
    2023-01-24
  • Unicorn Landing page
    Landing page //
    2023-09-12

Apache Tomcat features and specs

  • Open Source
    Apache Tomcat is an open-source software, which means it is freely available for use and modifications. This can significantly reduce the cost of ownership and allows for customization.
  • Community Support
    Being a widely-used open-source server, Tomcat has a large and active community of developers and users who contribute to its documentation, plugins, and forums, providing extensive support.
  • Lightweight
    Tomcat is designed to be a lightweight servlet container, making it faster and less resource-intensive compared to full-blown Java EE application servers.
  • Integration with Popular Frameworks
    Tomcat integrates well with popular Java frameworks such as Spring and Hibernate, making it easier for developers to deploy and manage web applications.
  • Easy to Set Up and Configure
    Tomcat is relatively easy to set up and configure, making it suitable for both development and production environments.
  • Frequent Updates
    Regular updates and patches are released to improve performance, security, and compatibility, ensuring the server is up-to-date with the latest web technologies.

Possible disadvantages of Apache Tomcat

  • Limited Functionality
    While Tomcat is a powerful servlet container, it lacks some of the advanced features found in full-fledged Java EE application servers, which might be necessary for complex enterprise applications.
  • Resource Management
    Tomcat's default configuration might not be suitable for high traffic web applications, requiring significant tweaking and tuning to handle heavy loads effectively.
  • Documentation Quality
    The documentation, while extensive, can sometimes be hard to navigate and understand, especially for beginners. This can slow down the learning curve.
  • Limited Built-in Tools
    Compared to other full-stack application servers, Tomcat comes with limited built-in tooling for monitoring, load balancing, and clustering, often requiring third-party solutions.
  • Security Concerns
    As with any open-source project, security vulnerabilities may emerge. It requires constant monitoring and timely updates to ensure security.
  • Lack of EJB Support
    Tomcat does not support Enterprise JavaBeans (EJB), limiting its use in scenarios where EJB is a crucial component of the architecture.

Unicorn features and specs

  • Performance
    Unicorn is designed to handle multiple concurrent connections and efficiently manage resources, providing improved performance for Ruby applications.
  • Concurrency
    With its multi-process architecture, Unicorn can handle multiple client requests simultaneously, which is ideal for multi-threaded or concurrent applications.
  • Robust Process Management
    Unicorn automatically manages process worker pools and can gracefully handle worker crashes, leading to more robust and reliable server performance.
  • Compatibility
    Unicorn works seamlessly with Rack applications and is compliant with popular web server standards, making it easy to integrate with existing Ruby on Rails applications.
  • Simplicity
    Unicorn's straightforward design focuses on simplicity and minimalistic architecture, reducing the need for extensive configuration.

Possible disadvantages of Unicorn

  • Memory Usage
    Unicorn uses a multi-process model, which can lead to higher memory consumption compared to multi-threaded servers, potentially increasing costs on memory-bound systems.
  • Non-Windows Platform
    Unicorn is designed to work primarily on Unix-like systems. It is not natively supported on Windows, limiting its use in cross-platform environments.
  • Limited Scalability
    Unicorn does not easily scale across multiple machines. It is best suited for applications running on a single server, as scaling out horizontally requires external tools and configurations.
  • Blocking I/O
    Since Unicorn uses a preforking model with blocking I/O, it may not be suitable for applications that require non-blocking, event-driven I/O operations.
  • Graceful Restart
    While Unicorn supports zero-downtime deployments, managing graceful restarts can be complex and might require additional configuration and handling.

Apache Tomcat videos

Introducing Apache Tomcat 8.5

More videos:

  • Review - Webinar: Introduction to Apache Tomcat 8
  • Review - Tcat - The Leading Enterprise Apache Tomcat Application Server

Unicorn videos

War Thunder: Tiger H1 Super Unicorn Review

More videos:

  • Review - War Thunder: OTOMATIC Super Unicorn Review
  • Review - M4A3 (76) HVSS Wannabe Unicorn Review

Category Popularity

0-100% (relative to Apache Tomcat and Unicorn)
Web And Application Servers
Application Server
83 83%
17% 17
Web Servers
80 80%
20% 20
Java
100 100%
0% 0

User comments

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Reviews

These are some of the external sources and on-site user reviews we've used to compare Apache Tomcat and Unicorn

Apache Tomcat Reviews

FOSS | Top 15 Web Servers 2021
Java programs are run using Apache Tomcat. To be more precise, it is a Java servlet – a Java software component that expands the functionality of a web server. Apache Tomcat, released under the Apache License version 2, is used by 0.1% of websites worldwide.
Source: www.zentao.pm
4 Open Source Application Servers (Comparison and Review)
Apache Tomcat is an open-source implementation of several Java technologies. It is the result of a collaboration of the finest developers worldwide. You can get involved with the development in a number of ways.
Source: shadow-soft.com
Top 5 open source web servers
Apache Tomcat is an open source Java servlet container that functions as a web server. A Java servlet is a Java program that extends the capabilities of a server. Although servlets can respond to any types of requests, they most commonly implement applications hosted on Web servers. Such web servlets are the Java counterpart to other dynamic web content technologies such as...
Source: opensource.com
Top 10 Open Source Java and JavaEE Application Servers
It is built upon a modular kernel powered by OSGi, and runs straight on top of the Apache Felix implementation. It is also capable of running with Equinox OSGi or Knopflerfish OSGi runtimes. HK2 abstracts the OSGi module system to provide components, which can also be viewed as services and injected into the run time and uses a derivative of Apache Tomcat as the servlet...

Unicorn Reviews

Unicorn vs. Puma vs. Passenger: which app server is right for you?
Puma and Passenger are equipped to handle slow clients. Unicorn cannot help with slow clients by itself: requests go directly to a worker process. Unicorn doesn't hide this. The Unicorn docs clearly state: "You should not allow unicorn to serve clients outside of your local network". However, you can get around by using Nginx as a reverse proxy and letting it buffer client...
Source: scoutapm.com

Social recommendations and mentions

Based on our record, Apache Tomcat seems to be a lot more popular than Unicorn. While we know about 17 links to Apache Tomcat, we've tracked only 1 mention of Unicorn. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

Apache Tomcat mentions (17)

  • Java News: WildFly 36, Spring Milestones, and Open Liberty Updates
    Versions 11.0.6 and 9.0.104 of Apache Tomcat deliver new features and improvements. The release notes can be found for both versions. - Source: dev.to / 27 days ago
  • Artifactory: Centralizing Artifact Management for DevOps Success
    Download and Install Tomcat Before downloading, confirm the latest Tomcat build package from the official website. - Source: dev.to / 7 months ago
  • How to Deploy Applications Using Tomcat on a Web Server
    First, download the latest version of Tomcat from the official Apache Tomcat website. Choose the version that suits your needs, typically the latest stable release. - Source: dev.to / 11 months ago
  • Spring Boot Monitoring with Open-Source Tools
    Manual instrumentation allows you to define your Spans within the code itself rather than relying on automatic instrumentation finding the entry point for a trace. Manual instrumentation is especially helpful for applications that don’t use an application server such as Tomcat, JBoss, or Jetty. - Source: dev.to / over 1 year ago
  • Issue with chatgpy
    99% is a huge exaggeration. Two essential deployment tools off the top of my head: Https://tomcat.apache.org/ Https://docs.jboss.org/author/display/AS71/Developer%20Guide.html. Source: about 2 years ago
View more

Unicorn mentions (1)

What are some alternatives?

When comparing Apache Tomcat and Unicorn, you can also consider the following products

Microsoft IIS - Internet Information Services is a web server for Microsoft Windows

LiteSpeed Web Server - LiteSpeed Web Server (LSWS) is a high-performance Apache drop-in replacement.

Apache HTTP Server - Apache httpd has been the most popular web server on the Internet since April 1996

XAMPP - XAMPP is a free and open-source cross-platform web server that is primarily used when locally developing web applications.

Phusion Passenger - Phusion Passenger is a multi-language (Ruby, Python, Node) web & app server which can integrate into Apache and Nginx

Eclipse Jetty - Jetty is a highly scalable modular servlet engine and http server that natively supports many modern protocols like SPDY and WebSockets.