[解決済み] ビューの描画が遅い原因を診断する

質問

いつから始まったのかわかりませんが、私のアプリ (開発用マシンでローカルに実行) で何か異常なことが起こっています。突然、次のようなメッセージが表示されるようになりました。

Started GET "/" for 127.0.0.1 at 2013-03-10 12:10:24 +1300
Processing by PagesController#home as HTML
  Rendered pages/home.html.erb within layouts/application (2.4ms)
Completed 200 OK in 3242ms (Views: 3241.4ms | ActiveRecord: 0.0ms)

ご覧のように、ホームページ (比較的シンプルなページ) を読み込むのに 3 秒かかっています......。私たちは、ハードなページの再読み込みを話しているわけではありません...他のページから再度 "home"リンクをクリックするだけです。

どこから始めればいいのかよくわかりませんが、これは私のapplication.rbです。

#config/boot.rb is loaded
require File.expand_path('../boot', __FILE__)

require 'rails/all'

if defined?(Bundler)
  Bundler.require(*Rails.groups(:assets => %w(development test)))
end

module Goodsounds
  class Application < Rails::Application
    config.encoding = "utf-8"
    config.filter_parameters += [:password]
    config.assets.initialize_on_precompile = false
    config.assets.enabled = true
    config.action_controller.assets_dir = "#{File.dirname(File.dirname(__FILE__))}/public"
    config.assets.version = '1.0'
    config.autoload_paths += Dir["#{Rails.root}/lib/modules"]
    config.assets.paths += Dir["#{Rails.root}/app/assets/fonts/*"]
    config.assets.precompile += %w( .svg .eot .woff .ttf ) 
  end
end

...そしてdev.rb。

Goodsounds::Application.configure do
  # Settings specified here will take precedence over those in config/application.rb
    Paperclip.options[:command_path] = "/usr/bin/"

    config.action_mailer.default_url_options = { :host => 'localhost:3000' }

  config.action_mailer.raise_delivery_errors = true

  # set delivery method to :smtp, :sendmail or :test
  config.action_mailer.delivery_method = :smtp

  # these options are only needed if you choose smtp delivery

  config.action_mailer.smtp_settings = { :address => "localhost", :port => 1025 }

  # In the development environment your application's code is reloaded on
  # every request. This slows down response time but is perfect for development
  # since you don't have to restart the web server when you make code changes.
  config.cache_classes = false

  # Log error messages when you accidentally call methods on nil.
  config.whiny_nils = true

  # Show full error reports and disable caching
  config.consider_all_requests_local       = true
  config.action_controller.perform_caching = false

  # Print deprecation notices to the Rails logger
  config.active_support.deprecation = :log

  # Only use best-standards-support built into browsers
  config.action_dispatch.best_standards_support = :builtin

  # Raise exception on mass assignment protection for Active Record models
  config.active_re
cord.mass_assignment_sanitizer = :strict

  # Log the query plan for queries taking more than this (works
  # with SQLite, MySQL, and PostgreSQL)
  config.active_record.auto_explain_threshold_in_seconds = 0.5

  # Do not compress assets
  config.assets.compress = false

  # Expands the lines which load the assets
  config.assets.debug = true
end

EDITです。

OK、これは私が新しいレリックで見ているものです。しかし、本当に私を助けることはありません。どんな考えですか？

あ、あとChromeのタイムラインから学んだこと。

Send Request - Details
Duration    0 (at 655 ms)
Resource    localhost
Request Method  GET

Receive Response - Details
Duration    0.043 ms (at 4.17 s)
Resource    localhost
Status Code 200
MIME Type   text/html

Receive Data - Details
Duration    176.329 ms (at 4.17 s)
Self Time   7.037 ms
CPU Time    176.329 ms
Aggregated Time 061.194 ms114.664 ms0.471 ms0
Resource    localhost
Encoded Data Length 303 Bytes
Used Heap Size  29.1 MB (+5.7 MB)

Finish Loading - Details
Duration    0 (at 4.35 s)
Resource    localhost

ところで、quiet_assets gemを無効にして、ターミナルで何が発見できるか見てみたのですが、やはり...役に立ちませんでした。

Started GET "/" for 127.0.0.1 at 2013-03-10 21:46:40 +1300
Processing by PagesController#home as HTML
  Rendered pages/home.html.erb within layouts/application (43.4ms)
Completed 200 OK in 3501ms (Views: 3480.9ms | ActiveRecord: 19.4ms)


Started GET "/assets/dataTables/jquery.dataTables.bootstrap.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /dataTables/jquery.dataTables.bootstrap.css - 304 Not Modified (11ms)


Started GET "/assets/chosen.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /chosen.css - 304 Not Modified (5ms)


Started GET "/assets/select2.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /select2.css - 304 Not Modified (4ms)


Started GET "/assets/autocomplete.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /autocomplete.css - 304 Not Modified (1ms)


Started GET "/assets/branches.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /branches.css - 304 Not Modified (2ms)


Started GET "/assets/bubbles.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bubbles.css - 304 Not Modified (1ms)


Started GET "/assets/business_show.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /business_show.css - 304 Not Modified (1ms)


Started GET "/assets/chunkyfive_font.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /chunkyfive_font.css - 304 Not Modified (1ms)


Started GET "/assets/consumer_show.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /consumer_show.css - 304 Not Modified (2ms)


Started GET "/assets/datatable_styling.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /datatable_styling.css - 304 Not Modified (1ms)


Started GET "/assets/datepicker.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /datepicker.css - 304 Not Modified (2ms)


Started GET "/assets/devise_links.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /devise_links.css - 304 Not Modified (1ms)


Started GET "/assets/dispenser_show.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /dispenser_show.css - 304 Not Modified (1ms)


Started GET "/assets/fonts.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /fonts.css - 304 Not Modified (1ms)


Started GET "/assets/forms.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /forms.css - 304 Not Modified (2ms)


Started GET "/assets/gmaps4rails.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /gmaps4rails.css - 304 Not Modified (1ms)


Started GET "/assets/jquery-ui-1.10.0.custom.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jquery-ui-1.10.0.custom.css - 304 Not Modified (2ms)


Started GET "/assets/jumbotrons.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jumbotrons.css - 304 Not Modified (1ms)


Started GET "/assets/layout.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /layout.css - 304 Not Modified (1ms)


Started GET "/assets/open_sans.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /open_sans.css - 304 Not Modified (2ms)


Started GET "/assets/popover.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /popover.css - 304 Not Modified (1ms)


Started GET "/assets/reviews.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /reviews.css - 304 Not Modified (1ms)


Started GET "/assets/spinner.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /spinner.css - 304 Not Modified (2ms)


Started GET "/assets/style_show.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /style_show.css - 304 Not Modified (2ms)


Started GET "/assets/style_show_reviews.css?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /style_show_reviews.css - 304 Not Modified (2ms)


Started GET "/assets/jquery.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jquery.js - 304 Not Modified (3ms)


Started GET "/assets/jquery_ujs.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jquery_ujs.js - 304 Not Modified (3ms)


Started GET "/assets/ui.custom.min.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /ui.custom.min.js - 304 Not Modified (1ms)


Started GET "/assets/bootstrap-transition.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-transition.js - 304 Not Modified (5ms)


Started GET "/assets/bootstrap-affix.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-affix.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap-alert.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-alert.js - 304 Not Modified (4ms)


Started GET "/assets/bootstrap-button.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-button.js - 304 Not Modified (5ms)


Started GET "/assets/bootstrap-carousel.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-carousel.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap-collapse.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-collapse.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap-dropdown.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-dropdown.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap-modal.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-modal.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap-scrollspy.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-scrollspy.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap-tab.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-tab.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap-tooltip.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-tooltip.js - 304 Not Modified (5ms)


Started GET "/assets/bootstrap-popover.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-popover.js - 304 Not Modified (52ms)


Started GET "/assets/bootstrap-typeahead.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap-typeahead.js - 304 Not Modified (3ms)


Started GET "/assets/bootstrap.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /bootstrap.js - 304 Not Modified (13ms)


Started GET "/assets/gmaps4rails/gmaps4rails.base.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /gmaps4rails/gmaps4rails.base.js - 304 Not Modified (1ms)


Started GET "/assets/gmaps4rails/gmaps4rails.bing.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /gmaps4rails/gmaps4rails.bing.js - 304 Not Modified (2ms)


Started GET "/assets/gmaps4rails/gmaps4rails.googlemaps.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /gmaps4rails/gmaps4rails.googlemaps.js - 304 Not Modified (2ms)


Started GET "/assets/gmaps4rails/gmaps4rails.mapquest.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /gmaps4rails/gmaps4rails.mapquest.js - 304 Not Modified (2ms)


Started GET "/assets/gmaps4rails/gmaps4rails.openlayers.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /gmaps4rails/gmaps4rails.openlayers.js - 304 Not Modified (2ms)


Started GET "/assets/jqueryplugins/addresspicker.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jqueryplugins/addresspicker.js - 304 Not Modified (2ms)


Started GET "/assets/jqueryplugins/browser_detect.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jqueryplugins/browser_detect.js - 304 Not Modified (3ms)


Started GET "/assets/jqueryplugins/charts.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jqueryplugins/charts.js - 304 Not Modified (2ms)


Started GET "/assets/jqueryplugins/jquery.alphanumeric.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jqueryplugins/jquery.alphanumeric.js - 304 Not Modified (1ms)


Started GET "/assets/jqueryplugins/jquery.formrestrict.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jqueryplugins/jquery.formrestrict.js - 304 Not Modified (2ms)


Started GET "/assets/jqueryplugins/jquery.lazyload.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jqueryplugins/jquery.lazyload.js - 304 Not Modified (1ms)


Started GET "/assets/jqueryplugins/raty.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /jqueryplugins/raty.js - 304 Not Modified (2ms)


Started GET "/assets/dataTables/jquery.dataTables.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /dataTables/jquery.dataTables.js - 304 Not Modified (13ms)


Started GET "/assets/dataTables/jquery.dataTables.bootstrap.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /dataTables/jquery.dataTables.bootstrap.js - 304 Not Modified (63ms)


Started GET "/assets/lib/abstract-chosen.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /lib/abstract-chosen.js - 304 Not Modified (12ms)


Started GET "/assets/lib/select-parser.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /lib/select-parser.js - 304 Not Modified (12ms)


Started GET "/assets/chosen.jquery.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /chosen.jquery.js - 304 Not Modified (8ms)


Started GET "/assets/chosen-jquery.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /chosen-jquery.js - 304 Not Modified (9ms)


Started GET "/assets/select2.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /select2.js - 304 Not Modified (7ms)


Started GET "/assets/highcharts.js?body=1" for 127.0.0.1 at 2013-03-10 21:46:44 +1300
Served asset /highcharts.js - 304 Not Modified (1ms)

ところで、redditでの提案に従って、私は資産をプリコンパイルし、サーバを実行しました。素晴らしい速度が見られました。

Processing by PagesController#home as HTML
Rendered pages/home.html.erb within layouts/application (1.1ms)
Completed 200 OK in 6ms (Views: 5.4ms | ActiveRecord: 0.0ms)

これが役に立つかどうかはわかりませんが、主な遅延はスタック内のこれらの2行のコードの間で起こっています。

From: /home/funkdified/.rvm/gems/ruby-1.9.3-p392@goodsounds/gems/actionpack-3.2.13.rc1/lib/action_controller/metal/implicit_render.rb @ line 5 ActionController::ImplicitRender#send_action:

    3: def send_action(method, *args)
    4:   ret = super
 => 5:   default_render unless response_body
    6:   ret
    7: end

[2] pry(#<PagesController>)> next

大幅な遅延

From: /home/funkdified/.rvm/gems/ruby-1.9.3-p392@goodsounds/gems/actionpack-3.2.13.rc1/lib/action_controller/metal/implicit_render.rb @ line 6 ActionController::ImplicitRender#send_action:

    3: def send_action(method, *args)
    4:   ret = super
    5:   default_render unless response_body
 => 6:   ret
    7: end

どのように解決するのですか？

OK、私はそれを（ついに）見つけ出した。私の実際の資産を変更することなく、私は今、これが開発であることを確認しています。

Started GET "/" for 127.0.0.1 at 2013-03-11 23:14:33 +1300
Processing by PagesController#home as HTML
Rendered pages/home.html.erb within layouts/application (1.3ms)

遅延の原因は config.assets.debug = true であることがわかりました。これを false に設定すると、問題が解決します。

Railsのコアチームが議論したような をデフォルトでオフにする というのがありますが、その考えはやめました。将来的には、development.rb のコメントセクションに、大幅な遅延の可能性についてユーザーに注意を促すようなことを書いてほしいです。

次のことを提案してもよいでしょうか。

# Expands the lines which load the assets 
# May cause significant delays in view rendering

凄い、私の呟きを聞いて レールを更新 !