Which is faster: MRI Ruby or JRuby?

Question

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

Answer 1

The answer depends on many variables.

But in general, Ruby 1.9 is faster than JRuby, but Ruby 1.8 is slower than JRuby.

e.g. according to the Computer Language Benchmarks Game:

• Ruby 1.9 vs JRuby
• Ruby 1.8 vs JRuby

Also, if your application is multi-threaded, JRuby may have some advantages over standard Ruby
(a.k.a. MRI)], depending on how many cores you have.