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A hard working Jetty based Rack server
Ruby Java
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Mizuno is a set of Jetty-powered running shoes for JRuby/Rack.

To use Mizuno with your Rack app:

gem install mizuno
cd /path/to/my/rack/app

...and you're off and running. You don't need to set up a Java web container for your Rack application to run under JRuby, because Mizuno works just like Mongrel, WEBRick, Thin, or any other standard Rack handler.

Mizuno is the fastest option for Rack applications on JRuby:

Mizuno: 6106.66 req/s (mean)
Jetty (via jruby-rack): 2011.67 req/s (mean)
Mongrel: 1479.15 req/sec (mean)

Mizuno also supports asynchronous request handling, via the Java Servlet 3.0 asynchronous processing mechanism

All the speed comes from Jetty 7; Mizuno just ties it to Rack through JRuby's Ruby/Java integration layer.

Note that Mizuno is NOT a direct replacement for jruby-rack or Warbler, because it doesn't produce WAR files or make any attempt to package a Rack application for installation in a Java web container.

There's also a few features that I have yet to implement:

  1. Add hooks for realtime monitoring of server performance.


Mizuno requires rjack-slf4j which provides a unified interface for Java/Ruby logging. Jetty auto-detect SLF4J's presence and logs there. A logging output provider must also be loaded. The minzuno script will load rjack-logback if found or otherwise fall back to rjack-slf4j/simple. If you are starting Mizuno through some other means than the mizuno script, you will need to load an output provider (see linked docs.)


Mizuno is licensed under the Apache Public License, version 2.0; see the LICENSE file for details, and was developed on behalf of Mad Wombat Software

Jetty is dual-licensed under the Eclipse and Apache open-source licenses, and its development is hosted by the Eclipse Foundation

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