在Memcache中缓存caches_action fragmens并在文件系统中缓存资产

在Heroku，Dalli gem和Memcachier上使用Rails 3.1.1 .

我正在尝试解决问题where keys disappear from Memcachier，为了做到这一点，我想确保只有来自我的caches_action的内容将缓存在内存缓存中 . 我想将我的资产（jpg等）缓存到其他地方 .

我认为它与this question是同一个问题，但是当我这样做时，即添加

config.action_dispatch.rack_cache = {
  :metastore    => Dalli::Client.new,
  :entitystore  => 'file:tmp/cache/rack/body',
  :allow_reload => false
}

到我的production.rb，它似乎并没有做任何事情 .

我的 production.rb 完整：

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

  # Code is not reloaded between requests
  config.cache_classes = true

  # Full error reports are disabled and caching is turned on
  config.consider_all_requests_local       = false
  config.action_controller.perform_caching = true

  # Disable Rails's static asset server (Apache or nginx will already do this)
  config.serve_static_assets = true

  # Compress JavaScripts and CSS
  config.assets.compress = true

  # Don't fallback to assets pipeline if a precompiled asset is missed
  config.assets.compile = true

  # Generate digests for assets URLs
  config.assets.digest = true

  # Defaults to Rails.root.join("public/assets")
  # config.assets.manifest = YOUR_PATH

  # Specifies the header that your server uses for sending files
  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for apache
  # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for nginx

  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
  # config.force_ssl = true

  # See everything in the log (default is :info)
  # config.log_level = :debug

  # Prepend all log lines with the following tags
  # config.log_tags = [ :subdomain, :uuid ]

  # Use a different logger for distributed setups
  # config.logger = ActiveSupport::TaggedLogging.new(SyslogLogger.new)

  # Use a different cache store in production
  config.cache_store = :dalli_store 

  config.action_dispatch.rack_cache = {
    :metastore    => Dalli::Client.new,
    :entitystore  => 'file:tmp/cache/rack/body',
    :allow_reload => false
  }  

  # Set expire header of 30 days for static files
  config.static_cache_control = "public, max-age=2592000" 

  # Enable serving of images, stylesheets, and JavaScripts from an asset server
  # config.action_controller.asset_host = "http://assets.example.com"

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

  # Disable delivery errors, bad email addresses will be ignored
  # config.action_mailer.raise_delivery_errors = false

  # Enable threaded mode
  # config.threadsafe!

  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
  # the I18n.default_locale when a translation can not be found)
  config.i18n.fallbacks = true

  # Send deprecation notices to registered listeners
  config.active_support.deprecation = :notify
end

缓存资产工作正常（获取缓存新鲜响应）和缓存这样的操作：

caches_action :show, :layout => false, :expires_in => 3.days

还在Rails缓存中创建一个缓存条目（虽然它们会在一段时间后消失） .

My question now is ：如果可能的话，我怎么能这样做只有我的caches_action片段最终存在于我的Memcache中（而不是我的资产）？

一个额外的问题是，你在我的produ.rb中看到了什么与众不同的东西吗？