[headius]

They're a mixed bag because they're benchmarking libraries more than they're benchmarking runtimes. Often the JRuby-specific versions of libraries (e.g. activerecord-jdbc) do not get the same performance attention as the ones for MRI, and as a result they perform worse.

I know this is small consolation, but everything in the JRuby ecosystem is continuing to improve every day. When there's specific reproducible cases where we're slower, we take them very seriously.