Struct.new VS Data.define

benchmark_define.rb

require 'benchmark/ips'

DataS = Struct.new(:encoder, :values) do # :nodoc:
  def hash
    [encoder, values].hash
  end
end

DataD = Data.define(:encoder, :values) do # :nodoc:
  def hash
    [encoder, values].hash
  end
end

DataDkw = Data.define

class DataDCkw < DataDkw
  def initialize(encoder:, values:)
    @encoder = encoder
    @values = values
  end
  def hash
    [@encoder, @values].hash
  end
end


Benchmark.ips do |x|
  x.report("Struct.new") do
    DataS.new("CSV", [1,2,3]).hash
  end

  x.report("Data.define") do
    DataD.new("CSV", [4,5,6]).hash
  end

  x.report("Data.define kw") do
    DataDCkw.new(encoder: "CSV", values: [7,8,9]).hash
  end

  x.compare!
end

=begin
Warming up --------------------------------------
          Struct.new   291.475k i/100ms
         Data.define   219.096k i/100ms
      Data.define kw   170.260k i/100ms
Calculating -------------------------------------
          Struct.new      2.930M (± 0.3%) i/s -     14.865M in   5.073303s
         Data.define      2.204M (± 0.4%) i/s -     11.174M in   5.070686s
      Data.define kw      1.703M (± 0.3%) i/s -      8.683M in   5.097443s

Comparison:
          Struct.new:  2930109.7 i/s
         Data.define:  2203663.3 i/s - 1.33x  slower
      Data.define kw:  1703469.8 i/s - 1.72x  slower
=end

Different output if we look only at initialization, but I think we do less.

require 'benchmark/ips'

DataS = Struct.new(:encoder, :values) do # :nodoc:
end

DataD = Data.define(:encoder, :values) do # :nodoc:
end

DataDkw = Data.define

class DataDCkw < DataDkw
  def initialize(encoder:, values:)
  end
end


Benchmark.ips do |x|
  x.report("Struct.new") do
    DataS.new("CSV", [1,2,3])
  end

  x.report("Data.define") do
    DataD.new("CSV", [4,5,6])
  end

  x.report("Data.define kw") do
    DataDCkw.new(encoder: "CSV", values: [7,8,9])
  end

  x.compare!
end

=begin
Warming up --------------------------------------
          Struct.new   667.338k i/100ms
         Data.define   387.392k i/100ms
      Data.define kw   417.789k i/100ms
Calculating -------------------------------------
          Struct.new      6.691M (± 0.3%) i/s -     34.034M in   5.086985s
         Data.define      3.856M (± 0.6%) i/s -     19.370M in   5.023972s
      Data.define kw      4.169M (± 1.0%) i/s -     20.889M in   5.010822s

Comparison:
          Struct.new:  6690531.8 i/s
      Data.define kw:  4169259.5 i/s - 1.60x  slower
         Data.define:  3855574.1 i/s - 1.74x  slower
=end