This is an Apache JMeter-based request benchmark of a trivial Rack application running on four JRuby-based servers, Aspen, Kirk, Trinidad and Mizuno.

Using JMeter on a separate machine on the local network, my MacBook Pro 2.53Ghz Core 2 Duo produced the following results (higher is better).

Reproducing the Benchmark

1. Install JRuby.
2. Run rake install to install all server gems and JMeter.
3. Start JMeter with rake jmeter.
4. Start the server of your choice with rake server[<server-name>].
5. (Optional) Start Visual VM and connect to the server to monitor memory, threads and CPU while the benchmark runs.
6. Start the benchmark with the "Run => Start" menu command.
7. Watch the benchmark in progress by selecting the "Summary Report" item in the tree.

A side note: if you're running JMeter on the same machine as the server, the 200 concurrent users run might overwhelm your machine and produce unreliable results. Pay attention to the error count -- any amount over 1-2% probably indicates either the server or your computer is topping out.

Submit your benchmark results as issues in the issue tracker!