For a while Phusion offered Ruby Enterprise Edition[1] which made improvements on the Ruby 1.8.7 interpreter including improvements such as:
> * A “copy-on-write friendly” garbage collector, capable of reducing Ruby on Rails applications’ memory usage by 33% on average.
> * The tcmalloc memory allocator, which lowers overall memory usage and boosts memory allocation speed. > * The ability to performance tune the garbage collector.
> * The MBARI patch set, for improved garbage collection efficiency.
> * Various analysis and debugging features.
They've since dropped support of it because:
> * A copy-on-write patch has recently been checked into Ruby 2.0.
> * Many of the patches in Ruby Enterprise Edition are simply not necessary in 1.9.
So it sounds like many of the improvements offered in Ruby Enterprise Edition 1.8.7 have been rolled into Ruby 2.0. Do you have any suggestions of what might be included in a Ruby Enterprise Edition 2.0?
[1] http://blog.phusion.nl/category/ruby-enterprise-edition/