A rack server with built upon Vertx

View the Project on GitHub isaiah/jubilee

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A vertx module that run rack applications.

Get started

Please checkout the wiki page before you proceed.

Add the following snippet to $VERTX\_HOME/conf/langs.properties


Make sure JRUBY_HOME is correctly set, and rack gem is install before proceed.

Then run the rackup file as a normal verticle,

vertx run config.ru

Build from source

Checkout the source and run the following command in the root directory of the project:

mvn install

Event Bus

Event Bus is a pub/sub mechanism, it can be used from server to server, server to client and client to client, with the same API! You can use it to build living real time web application.


Assume necessary javascript files are loaded in the page (they can be found here), run rack application with the following config:

$ cat config.json
{ "host": "",
  "port": 8080,
  "event_bus": "/eventbus"
$ vertx run config.ru -conf config.json

In one browser:

var eb = new vertx.EventBus("/eventbus");
eb.registerHandler("test", function(data){

In another:

var eb = new vertx.EventBus("/eventbus");
eb.send("test", "hello, world");

In the previous tab it should print the greetings you just sent.

For more advanced examples, please checkout the chatapp.

Performance Tuning

If you're creating a lot of connections to a Jubilee(Vert.x) server in a short period of time, e.g. benchmarking with tools like wrk, you may need to tweak some settings in order to avoid the TCP accept queue getting full. This can result in connections being refused or packets being dropped during the handshake which can then cause the client to retry.

A classic symptom of this is if you see long connection times just over 3000ms at your client.

How to tune this is operating system specific but in Linux you need to increase a couple of settings in the TCP / Net config (10000 is an arbitrarily large number)

sudo sysctl -w net.core.somaxconn=10000
sudo sysctl -w net.ipv4.tcp_max_syn_backlog=10000

For other operating systems, please consult your operating system documentation.


All kinds of contributions are welcome.

File an issue here if you encounter any problems. Or if you prefer to fix by yourself:

  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request




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