Rails 4.2 应用程序开发速度非常慢答案

【问题标题】：Rails 4.2 app very slow in developmentRails 4.2 应用程序开发速度非常慢
【发布时间】：2017-05-27 22:41:33
【问题描述】：

这几天我一直在用头撞墙。我的应用程序在开发模式下运行速度非常慢。大量时间用于提供资产（尤其是图像）。每个请求都非常慢，加载一个简单的 50kb jpeg 需要 7 秒。总页面加载时间可能长达几分钟...

我怀疑有一个自动加载代码的链接，因为当我打开类缓存时，我的东西加载速度要快得多（最多几百毫秒）。但这不是一个解决方案，因为我需要编写代码，所以每次进行更改时都无法重新启动服务器。

这是我的配置/development.rb

Rails.application.configure do
  # Settings specified here will take precedence over those in config/application.rb.

  # 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

  # Do not eager load code on boot.
  config.eager_load = false

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

  # Don't care if the mailer can't send.
  config.action_mailer.raise_delivery_errors = false

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

  # Raise an error on page load if there are pending migrations.
  config.active_record.migration_error = :page_load

  # Debug mode disables concatenation and preprocessing of assets.
  # This option may cause significant delays in view rendering with a large
  # number of complex assets.
  config.assets.debug = false

  # Asset digests allow you to set far-future HTTP expiration dates on all assets,
  # yet still be able to expire them through the digest params.
  config.assets.digest = true

  # Adds additional error checking when serving assets at runtime.
  # Checks for improperly declared sprockets dependencies.
  # Raises helpful error messages.
  config.assets.raise_runtime_errors = true

  # Raises error for missing translations
  # config.action_view.raise_on_missing_translations = true

  config.action_mailer.default_url_options = { host: '127.0.0.1', port: 3000 }
  # email sending process
  config.action_mailer.perform_deliveries = true
  config.action_mailer.delivery_method = :test
  # Defaults to:
  # config.action_mailer.sendmail_settings = {
  #   location: '/usr/sbin/sendmail',
  #   arguments: '-i -t'
  # }
  config.action_mailer.perform_deliveries = true
  config.action_mailer.raise_delivery_errors = true
  config.action_mailer.default_options = {from: 'no-reply@example.com'}
  config.web_console.whitelisted_ips = '0.0.0.0/0.0.0.0'


end

和初始化器/assets.rb

# Be sure to restart your server when you modify this file.

# Version of your assets, change this if you want to expire all your assets.
Rails.application.config.assets.version = '1.0'
# Rails.application.config.assets.precompile += %w( jquery.Jcrop.min.scss )
# Rails.application.config.assets.precompile += %w( jquery.Jcrop.min.js )
# Rails.application.config.assets.precompile += %w( flat-ui.css.bak )
# Rails.application.config.assets.precompile += %w( bootsrap.css.map)
# Add additional assets to the asset load path
# Rails.application.config.assets.paths << Emoji.images_path

# Precompile additional assets.
# application.js, application.scss, and all non-JS/CSS in app/assets folder are already added.
# Rails.application.config.assets.precompile += %w( search.js )

Dir.glob("#{Rails.root}/app/assets/images/**/").each do |path|
  Rails.application.config.assets.paths << path
end

任何见解将不胜感激！

【问题讨论】：

一个全新的应用程序是否表现出相同的行为？请求单一资产怎么样？您使用什么方法启动应用程序？你在什么操作系统上？您在此处发布的这些文件几乎与问题无关。
你可以试试config.assets.debug = true in development.rb 吗？
尝试预编译资产，有时会有帮助

标签： ruby-on-rails ruby ruby-on-rails-4 asset-pipeline autoload

【解决方案1】：

您的应用程序中可能会发生许多问题，例如它可能是 N+1 查询或一些慢代码、对其他站点的 HTTP 查询或大型资产包。所以我建议使用分析器，它会在你的代码中显示瓶颈。请参阅下面的流行分析器列表：

https://github.com/glassechidna/stackprofiler

https://github.com/ruby-prof/ruby-prof

您可以在此处找到其他有用的链接：

https://awesome-ruby.com/#-profiler-and-optimization

【讨论】：