ruby-on-rails - 诊断 View 渲染缓慢的原因

Question

我不确定这是什么时候开始的，但我的应用程序中发生了一些不寻常的事情(在开发计算机上本地运行)。突然我看到这样的消息:

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)

正如您所看到的，加载主页(一个相对简单的页面)需要 3 秒......我们不是在谈论硬页面重新加载......只需从另一个页面再次单击“主页”链接即可。

不太确定从哪里开始，但这是我的 application.rb:

#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

...和 ​​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

编辑:

好的，这是我在新遗物上看到的内容。但并没有真正帮助我。有什么想法吗？

哦，还有我从 Chrome 时间轴中学到的东西:

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

顺便说一句，我禁用了 Quiet_assets gem 来看看我可以在终端中发现什么......再次......没有帮助:

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)

顺便说一句，根据 reddit 上的建议，我预编译了 Assets 并运行了服务器。看到惊人的速度:

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)

好吧，不确定这是否提供任何帮助，但主要的延迟发生在堆栈中的这两行代码之间:

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

严重延迟

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

Answer 1

好吧，我终于明白了。在不改变我的任何实际 Assets 的情况下，我现在看到这就是开发:

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)

事实证明，延迟是由development.rb 内部的config.assets.debug = true 引起的。将其设置为 false 可以解决该问题。

看起来 Rails 核心团队正在争论 turning this off by default ，但决定反对这个想法。将来，我希望看到他们在development.rb 的评论部分添加一些内容，以提醒用户可能会出现严重延迟。

我可以提出以下建议:

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

太好了，他们听到我嘀咕了updated rails !