I have an application on Heroku and i am using Amazon S3 for storing images. I have used all Cache technics i know but seems images load too slow and it's putting off some users.

At the moment users get

```
/media/W1siZiIsIjIwMTQvMDIvMjEvMjMvMjAvMDQvNTY1L01pa2VfOTIzMi5qcGciXV0/Mike_150.jpg?sha=d8993be2

```

According to [instructions](http://markevans.github.io/dragonfly/cache/#serving-remotely--directly-from-the-datastore-) one has to use 

```
Dragonfly.app.remote_url_for(uid)

```

and they will get 

```
http://my-bucket.s3.amazonaws.com/2011/04/01/03/03/05/243/file.jpg

```

However when i add this line, nothing happens. 

```
#require 'dragonfly/s3_data_store'
require 'dragonfly'

# Configure
Dragonfly.app.configure do
  plugin :imagemagick

  protect_from_dos_attacks true
  secret "2558d89a83f18f6da793e3b6dccc888c17642563e9ddedf456356f4c2d79"

  url_format '/media/:job/:name'

  response_header 'Cache-Control', 'public, max-age=3600'                    # You can set custom response headers
  response_header 'Cache-Control' do |job, request, headers|    # either directly or with a block
    job.image? ? "public, max-age=10000000" : "private"         # setting to nil removes the header
  end

  allow_legacy_urls true

  if Rails.env.test? || Rails.env.development?
    datastore :file,
              root_path: Rails.root.join('public/system/dragonfly', Rails.env),
              server_root: Rails.root.join('public')
  else
    datastore :s3,
              bucket_name: ENV['S3_BUCKET_NAME'],
              access_key_id: ENV['S3_KEY'],
              secret_access_key: ENV['S3_SECRET'],
              url_scheme: 'http',
              url_host: 'mybucket.s3.amazonaws.com'

  end

end

# Logger
Dragonfly.logger = Rails.logger

Dragonfly.app.remote_url_for(uid)

# Mount as middleware
Rails.application.middleware.use Dragonfly::Middleware

# Add model functionality
if defined?(ActiveRecord::Base)
  ActiveRecord::Base.extend Dragonfly::Model
  ActiveRecord::Base.extend Dragonfly::Model::Validations
end

```

* What am i doing wrong?
* Does services files remote url change the app performance?