Hello, Rodrigo.

To be honest, I'm not familiar very much with JRuby,
but I've heard that on JRuby Thread can be executed truly parallel.
On the other hand, MRI has GVL and cpu bounded calculation could be
executed only concurrently, I means threads share a cpu core with time slicing.
So if there're many cpu cores in your environment, cpu bounded multi
threaded code
might be executed faster on JRuby than on MRI.

I'm afraid I might misunderstand the point.
I hope someone expert at JRuby/MRI give a more correct comment.

Regards,