Test for efficient sorting of an array of hashes

sorting.rb

require 'benchmark'

class EntryHash < Hash
  def <=>(other)
    self[:value] <=> (other && other[:value] || 0)
  end
end



10.times do |i|

  num = 100_000 * (i+1)

  plain_array1 = (1..num).map do |i|
    { :id => i, :value => rand(50) }
  end
  plain_array2 = plain_array1.dup

  object_array1 = plain_array1.map do |old|
    e = EntryHash.new
    e[:id]    = old[:id]
    e[:value] = old[:value]
    e
  end


  p :with => num
  Benchmark.bm do |x|
    x.report("inline block with sort!    ") do
      plain_array1.sort! do |a, b|
        (a && a[:value] || 0) <=> (b && b[:value] || 0)
      end
    end

    x.report("inline block with sort_by! ") do
      plain_array2.sort_by! do |a, b|
        (a && a[:value] || 0) <=> (b && b[:value] || 0)
      end
    end

    x.report("entry method with sort!    ") do
      object_array1.sort!
    end
  end
end

## Result:
#
# {:with=>100000}
#        user     system      total        real
# inline block with sort!      0.200000   0.000000   0.200000 (  0.197349)
# inline block with sort_by!   0.030000   0.000000   0.030000 (  0.061152)
# entry method with sort!      0.220000   0.000000   0.220000 (  0.221882)
# {:with=>200000}
#        user     system      total        real
# inline block with sort!      0.410000   0.000000   0.410000 (  0.423499)
# inline block with sort_by!   0.130000   0.000000   0.130000 (  0.123960)
# entry method with sort!      0.470000   0.000000   0.470000 (  0.474395)
# {:with=>300000}
#        user     system      total        real
# inline block with sort!      0.620000   0.010000   0.630000 (  0.626362)
# inline block with sort_by!   0.180000   0.010000   0.190000 (  0.275429)
# entry method with sort!      0.680000   0.000000   0.680000 (  0.684978)
# {:with=>400000}
#        user     system      total        real
# inline block with sort!      0.820000   0.000000   0.820000 (  0.832784)
# inline block with sort_by!   0.240000   0.010000   0.250000 (  0.366189)
# entry method with sort!      0.920000   0.000000   0.920000 (  0.923894)
# {:with=>500000}
#        user     system      total        real
# inline block with sort!      1.110000   0.000000   1.110000 (  1.109297)
# inline block with sort_by!   0.160000   0.000000   0.160000 (  0.315537)
# entry method with sort!      1.200000   0.000000   1.200000 (  1.206631)
# {:with=>600000}
#        user     system      total        real
# inline block with sort!      1.330000   0.000000   1.330000 (  1.337569)
# inline block with sort_by!   0.380000   0.000000   0.380000 (  0.378962)
# entry method with sort!      1.460000   0.000000   1.460000 (  1.463542)
# {:with=>700000}
#        user     system      total        real
# inline block with sort!      1.460000   0.000000   1.460000 (  1.461316)
# inline block with sort_by!   0.430000   0.020000   0.450000 (  0.444706)
# entry method with sort!      1.620000   0.000000   1.620000 (  1.630328)
# {:with=>800000}
#        user     system      total        real
# inline block with sort!      1.790000   0.000000   1.790000 (  1.789210)
# inline block with sort_by!   0.520000   0.000000   0.520000 (  0.763954)
# entry method with sort!      1.960000   0.000000   1.960000 (  1.971014)
# {:with=>900000}
#        user     system      total        real
# inline block with sort!      1.950000   0.010000   1.960000 (  1.971329)
# inline block with sort_by!   0.580000   0.000000   0.580000 (  0.855665)
# entry method with sort!      2.160000   0.000000   2.160000 (  2.159218)
# {:with=>1000000}
#        user     system      total        real
# inline block with sort!      2.410000   0.010000   2.420000 (  2.414475)
# inline block with sort_by!   0.660000   0.020000   0.680000 (  0.992156)
# entry method with sort!      2.650000   0.000000   2.650000 (  2.654844)