The benchmarks at https://github.com/fastruby/fast-ruby are mostly faster in JRuby but there are a few outliers. Since most of these are benchmarks of core class method performance (mostly native code) we should investigate and see if there's improvements possible.

I am running the full set of benchmarks with the following script:

files = Dir["code/**/*.rb"]
files.each_with_index {|file, i|
  puts "#{i+1}/#{files.size}: #{file}"
  system "jruby #{file}"
  system "/Users/headius/.rubies/ruby-3.4.7/bin/ruby --jit #{file}"
}

Some of these might catch up with more warmup time, and I'm pretty sure my system was throttling. We should investigate each individually.

Complete output: https://gist.github.com/headius/15413f657dad8d83c474114f8f9cf26a

Cases to fix: