bench.rb

require 'benchmark/ips'

Benchmark.ips do |x|
  x.report "Hash" do |loop|
    {foo: 42, bar: "hello", baz: "test"}
  end
end

Before

$ ./miniruby -v -Ilib -I../benchmark-ips/lib  ~/tmp/bench.rb
ruby 2.5.0dev (2017-08-20 trunk 59394) [x86_64-linux]
Warming up --------------------------------------
                Hash    98.244k i/100ms
Calculating -------------------------------------
                Hash    113.432B (±11.9%) i/s -    358.198B in   3.776462s

After

$ ./miniruby -v -Ilib -I../benchmark-ips/lib  ~/tmp/bench.rb
ruby 2.5.0dev (2017-08-20 trunk 59394) [x86_64-linux]
Warming up --------------------------------------
                Hash   122.583k i/100ms
Calculating -------------------------------------
                Hash    183.803B (±20.1%) i/s -    496.602B in   3.469529s

To be continued to RubyKaigi 2017