Hash Serialisation in Ruby between Marshal, JSON and YAML

benchmark.rb

my_hash = { symbol_key: 'string value', 'string key' => :symbol_value, 123 => 456, nil => true }

def do_this #&blk
  last_result = nil
  (1..10_000).map { |i| last_result = yield(i) }
  last_result
end

def factor(this, compared_to_this, precision=2)
  (this / compared_to_this).round(precision)
end

require "benchmark"
Benchmark.bm(7) do |x|
  result = nil

  marshal_run = x.report("Marshal:")  { result = do_this { Marshal.load( Marshal.dump(my_hash) ) } }.total
  puts result.inspect

  json_run = x.report("JSON:")     { result = do_this { JSON.parse(   JSON.dump(my_hash) )    } }.total
  puts result.inspect

  yaml_run = x.report("YAML:")     { result = do_this { YAML.load(    YAML.dump(my_hash) )    } }.total
  puts result.inspect

  puts "Compared to Marshal, JSON is #{factor(json_run, marshal_run)} slower and YAML is #{factor(yaml_run, marshal_run)} slower."
end

-----

              user     system      total        real
Marshal:  0.060000   0.010000   0.070000 (  0.054295)
{:symbol_key=>"string value", "string key"=>:symbol_value, 123=>456, nil=>true}
JSON:     0.160000   0.010000   0.170000 (  0.175384)
{"symbol_key"=>"string value", "string key"=>"symbol_value", "123"=>456, ""=>true}
YAML:     2.690000   0.120000   2.810000 (  2.806745)
{:symbol_key=>"string value", "string key"=>:symbol_value, 123=>456, nil=>true}
Compared to Marshal, JSON is 2.43 slower and YAML is 40.14 slower.