jbuilder vs ActiveModel::Serializers

.gitignore

log/

benchmark.rb

require_relative "setup"

require 'benchmark/ips'

class MoviesController < ApplicationController
  append_view_path "."

  def controller_path
    ""
  end

  movie = Movie.new(
    title: "Dawn of the Planet of the Apes",
    year: 2014,
    released: 1405062000,
    url: "http://trakt.tv/movie/dawn-of-the-planet-of-the-apes-2014",
    trailer: "http://youtube.com/watch?v=3wMnftb_RI4",
    runtime: 130,
    tagline: "One last chance for peace.",
    overview: "A group of scientists in San Francisco struggle to stay alive in the aftermath of a plague that is wiping out humanity, while Caesar tries to maintain dominance over his community of intelligent apes.",
    certification: "PG-13",
    imdb_id: "tt2103281",
    tmdb_id: "119450",
    poster: "http://slurm.trakt.us/images/posters_movies/211624.4.jpg",
    images: {
      poster: "http://slurm.trakt.us/images/posters_movies/211624.4.jpg",
      fanart: "http://slurm.trakt.us/images/fanart_movies/211624.4.jpg"
    },
    watchers: 33,
    ratings: {
      percentage: 80,
      votes: 1528,
      loved: 1456,
      hated: 72
    },
    genres: ["Action", "Drama", "Science Fiction", "Thriller"]
  )

  MOVIES = Array.new(15, movie)

  def jbuilder
    @movies = MOVIES
  end

  def asm
    render text: ActiveModel::ArraySerializer.new(MOVIES, each_serializer: MovieSerializer).to_json
  end
end

Benchmark.ips do |x|
  env = {
    "REQUEST_METHOD" => "GET",
    "HTTP_ACCEPT"    => "application/json",
    "rack.input"     => StringIO.new,
  }

  x.report 'jbuilder' do
    MoviesController.action(:jbuilder).call(env)
  end

  x.report 'AM::Serializers' do
    MoviesController.action(:asm).call(env)
  end

  x.compare!
end

Gemfile

source 'https://rubygems.org'

gem 'sqlite3'
gem 'railties', '~> 4.2.0'
gem 'actionpack', '~> 4.2.0'
gem 'activerecord', '~> 4.2.0'
gem 'active_model_serializers'
gem 'jbuilder'
gem 'benchmark-ips'

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    actionpack (4.2.0)
      actionview (= 4.2.0)
      activesupport (= 4.2.0)
      rack (~> 1.6.0)
      rack-test (~> 0.6.2)
      rails-dom-testing (~> 1.0, >= 1.0.5)
      rails-html-sanitizer (~> 1.0, >= 1.0.1)
    actionview (4.2.0)
      activesupport (= 4.2.0)
      builder (~> 3.1)
      erubis (~> 2.7.0)
      rails-dom-testing (~> 1.0, >= 1.0.5)
      rails-html-sanitizer (~> 1.0, >= 1.0.1)
    active_model_serializers (0.9.3)
      activemodel (>= 3.2)
    activemodel (4.2.0)
      activesupport (= 4.2.0)
      builder (~> 3.1)
    activerecord (4.2.0)
      activemodel (= 4.2.0)
      activesupport (= 4.2.0)
      arel (~> 6.0)
    activesupport (4.2.0)
      i18n (~> 0.7)
      json (~> 1.7, >= 1.7.7)
      minitest (~> 5.1)
      thread_safe (~> 0.3, >= 0.3.4)
      tzinfo (~> 1.1)
    arel (6.0.0)
    benchmark-ips (2.1.1)
    builder (3.2.2)
    erubis (2.7.0)
    i18n (0.7.0)
    jbuilder (2.2.6)
      activesupport (>= 3.0.0, < 5)
      multi_json (~> 1.2)
    json (1.8.2)
    loofah (2.0.1)
      nokogiri (>= 1.5.9)
    mini_portile (0.6.2)
    minitest (5.5.1)
    multi_json (1.10.1)
    nokogiri (1.6.6.2)
      mini_portile (~> 0.6.0)
    rack (1.6.0)
    rack-test (0.6.3)
      rack (>= 1.0)
    rails-deprecated_sanitizer (1.0.3)
      activesupport (>= 4.2.0.alpha)
    rails-dom-testing (1.0.5)
      activesupport (>= 4.2.0.beta, < 5.0)
      nokogiri (~> 1.6.0)
      rails-deprecated_sanitizer (>= 1.0.1)
    rails-html-sanitizer (1.0.1)
      loofah (~> 2.0)
    railties (4.2.0)
      actionpack (= 4.2.0)
      activesupport (= 4.2.0)
      rake (>= 0.8.7)
      thor (>= 0.18.1, < 2.0)
    rake (10.4.2)
    sqlite3 (1.3.10)
    thor (0.19.1)
    thread_safe (0.3.4)
    tzinfo (1.2.2)
      thread_safe (~> 0.1)

PLATFORMS
  ruby

DEPENDENCIES
  actionpack (~> 4.2.0)
  active_model_serializers
  activerecord (~> 4.2.0)
  benchmark-ips
  jbuilder
  railties (~> 4.2.0)
  sqlite3

jbuilder.json.jbuilder

json.array! @movies do |movie|
  json.extract! movie, :title, :year, :released, :url, :trailer,
                       :runtime, :tagline, :overview, :certification,
                       :imdb_id, :tmdb_id, :poster, :images, :watchers,
                       :ratings, :genres
end

setup.rb

require 'bundler/setup'
Bundler.require

require 'sqlite3'
require 'rails'
require 'active_record'
require 'active_model_serializers'
require 'action_controller'
require 'action_view'
require 'jbuilder'
require 'jbuilder/railtie'

# config
app = Class.new(Rails::Application)
app.config.secret_token = '3b7cd727ee24e8444053437c36cc66c4'
app.config.session_store :cookie_store, :key => '_myapp_session'
app.config.active_support.deprecation = :log
app.config.eager_load = false

# Rais.root
app.config.root = File.dirname(__FILE__)
Rails.backtrace_cleaner.remove_silencers!
app.initialize!

ActiveRecord::Base.configurations = {'test' => {adapter: 'sqlite3', database: ':memory:'}}
ActiveRecord::Base.establish_connection :test

class Movie < ActiveRecord::Base
  serialize :images, Hash
  serialize :ratings, Hash
  serialize :genres, Array
end

class CreateMovies < ActiveRecord::Migration
  def self.up
    create_table :movies do |t|
      t.string :title
      t.integer :year
      t.integer :released
      t.string :url
      t.string :trailer
      t.integer :runtime
      t.string :tagline
      t.text :overview
      t.string :certification
      t.string :imdb_id
      t.string :tmdb_id
      t.string :poster
      t.text :images
      t.integer :watchers
      t.text :ratings
      t.text :genres

      t.timestamps
    end
  end
end

ActiveRecord::Migration.verbose = false
CreateMovies.up

class MovieSerializer < ActiveModel::Serializer
  attributes :title, :year, :released, :url, :trailer,
             :runtime, :tagline, :overview, :certification,
             :imdb_id, :tmdb_id, :poster, :images, :watchers,
             :ratings, :genres
end

class ApplicationController < ActionController::Base
end

Result:

$ mkdir movies && mv jbuilder.json.jbuilder movies/
$ bundle exec ruby benchmark.rb 
Calculating -------------------------------------
            jbuilder    24.000  i/100ms
     AM::Serializers    32.000  i/100ms
-------------------------------------------------
            jbuilder    255.508  (± 7.4%) i/s -      1.272k
     AM::Serializers    337.855  (± 7.7%) i/s -      1.696k

Comparison:
     AM::Serializers:      337.9 i/s
            jbuilder:      255.5 i/s - 1.32x slower

Upgraded Rails to 4.2 and tried again:

$ mkdir movies && mv jbuilder.json.jbuilder movies/
$ bundle exec ruby benchmark.rb 
Calculating -------------------------------------
            jbuilder    24.000  i/100ms
     AM::Serializers    23.000  i/100ms
-------------------------------------------------
            jbuilder    240.349  (±10.4%) i/s -      1.200k
     AM::Serializers    285.601  (±14.0%) i/s -      1.403k

Comparison:
     AM::Serializers:      285.6 i/s
            jbuilder:      240.3 i/s - 1.19x slower

They seem no much difference on perfermance