Which is faster: MRI Ruby or JRuby?

ruby-on-rails ruby performance jruby
ses picture ses · Feb 4, 2011 · Viewed 25.9k times · Source

If I am using Ruby on Rails, should I install MRI/YARV Ruby or JRuby? Which is faster?

Answer

jc00ke picture jc00ke · Nov 19, 2012

Recent benchmarks put JRuby in the lead, followed by MagLev, Rubinius, then MRI.

Benchmarking is tricky. The Ruby Benchmark Suite is what most use to benchmark Ruby. If you remove any benchmarks that fail across any implementation, you get the following graph.

RBS

Notice I used the geometric mean. This is a better indicator of average performance as it normalizes outliers and machine specs.

The best benchmark you can run will be specific to your app. If you are looking for overall performance, you'll likely want to use real threads, so Rubinius or JRuby are your only real choices.

Also, each implementation is fast at different things. MRI is very fast at starting up, so it's good for scripts. For longer-running applications (like a web application) Rubinius or JRuby will generally perform better than MRI.

Related questions

How to enable compression in Ruby on Rails?

I posted a similar question here Serving Compressed Assets in Heroku with Rack-Zippy but decided to give up on that service, since I couldn't get it to work. I ran PageSpeed Insights on my website to determine the speed of …

Read More
When to use memoization in Ruby on Rails

In mid July 2008 Memoization was added to Rails core. A demonstration of the usage is here. I have not been able to find any good examples on when methods should be memoized, and the performance implications of each. This blog …

Read More
How to get a random number in Ruby

How do I generate a random number between 0 and n?

Read More