New Relic Ruby Agent¶ ↑
New Relic is a performance management system, developed by New Relic, Inc (www.newrelic.com). It provides you with deep information about the performance of your Rails or Ruby application as it runs in production. The New Relic Ruby Agent is dual-purposed as a either a Gem or a Rails plugin, hosted on github.
The New Relic Ruby Agent runs in one of two modes:
Production Mode Low overhead instrumentation that captures detailed information on your application running in production and transmits them to newrelic.com where you can monitor them in real time.
Developer Mode A Rack middleware
that maps /newrelic
to an application for showing detailed
performance metrics on a page by page basis. Installed automatically in Rails applications.
Supported Environments¶ ↑
An up-to-date list of Ruby versions and frameworks for the latest agent can be found on our docs site.
You can also monitor non-web applications. Refer to the “Other Environments” section under “Getting Started”.
Contributing Code¶ ↑
We welcome code contributions (in the form of pull requests) from our user community. Before submitting a pull request please review GUIDELINES_FOR_CONTRIBUTING.
Following these helps us efficiently review and incorporate your contribution and avoid breaking your code with future changes to the agent.
Getting Started¶ ↑
Add the Ruby Agent to your project's Gemfile.
gem 'newrelic_rpm'
To monitor your applications in production, create an account at newrelic.com/ . There you can sign up for a free Lite account or one of our paid subscriptions.
Once you receive the welcome email with a license key and
newrelic.yml
file, you can copy the newrelic.yml
file into your app config directory OR can generate the file manually with
command:
newrelic install --license_key="YOUR_KEY" "My application"
The initial configuration is done in the newrelic.yml
file.
This file is by default read from the config
directory of the
application root and is subsequently searched for in the application root
directory, and then in a ~/.newrelic
directory. Once
you're up and running you can enable Server Side Config and manage your
newrelic configuration from the web UI.
Rails Installation¶ ↑
You can install the agent as a Gem:
For Bundler:
Add the following line to your Gemfile:
gem 'newrelic_rpm'
For Rails 2.x without Bundler:
edit environment.rb
and add to the initalizer block:
config.gem "newrelic_rpm"
Sinatra Installation¶ ↑
To use the Ruby Agent with a Sinatra app, add
require 'newrelic_rpm'
in your Sinatra app, below the Sinatra require directive.
Then make sure you set RACK_ENV
to the environment
corresponding to the configuration definitions in the newrelic.yml file;
e.g., development, staging, production, etc.
To use Developer Mode in Sinatra, add
NewRelic::Rack::DeveloperMode
to the middleware stack. See the
config.ru
sample below.
Other Environments¶ ↑
You can use the Ruby Agent to monitor any Ruby application. Add
require 'newrelic_rpm'
to your startup sequence and then manually start the agent using
NewRelic::Agent.manual_start
For information about instrumenting pure Rack applications, see our Rack middlewares documentation.
Refer to the New Relic’s Docs for details on how to monitor other web frameworks, background jobs, and daemons.
The Ruby Agent provides an API that allows custom instrumentation of additional frameworks. You can find a list of community created intrumentation plugins (e.g. newrelic-redis) in the extends_newrelic_rpm project.
Developer Mode¶ ↑
When running the Developer Mode, the Ruby Agent will track the performance of every HTTP request serviced by your application, and store in memory this information for the last 100 HTTP transactions.
To view this performance information, including detailed SQL statement
analysis, open /newrelic
in your web application. For instance
if you are running mongrel or thin on port 3000, enter the following into
your browser:
http://localhost:3000/newrelic
Developer Mode is only initialized if the developer_mode
setting in the newrelic.yml file is set to true. By default, it is turned
off in all environments but development
.
Developer Mode in Rails¶ ↑
Developer Mode is available automatically in Rails
Applications based on Rails 2.3 and later. No
additional configuration is required. When your application starts and
developer_mode
is enabled, the Ruby Agent injects a middleware
into your Rails middleware stack.
For earlier versions of Rails that support Rack, you can use a config.ru
as below.
Developer Mode in Rack Applications¶ ↑
Developer Mode is available for any Rack based application such as Sinatra by installing the NewRelic::Rack::DeveloperMode middleware. This middleware passes all requests that do not start with /newrelic.
Here's an example entry for Developer Mode in a config.ru
file:
require 'new_relic/rack/developer_mode' use NewRelic::Rack::DeveloperMode
Production Mode¶ ↑
When your application runs in the production environment, the New Relic agent runs in production mode. It connects to the New Relic service and sends deep performance data to the UI for your analysis. To view this data, log in to rpm.newrelic.com.
NOTE: You must have a valid account and license key to view this data online. Refer to instructions in Getting Started.
Recording Deploys¶ ↑
The Ruby Agent supports recording deployments in New Relic via a command line tool or Capistrano recipes. For more information on these features see our deployment documentation for more information.
Support¶ ↑
You can find more detailed documentation on our website, and specifically in the Ruby category.
If you can't find what you're looking for there, reach out to us on our support site or our community forum and we'll be happy to help you.
Also available is community support on IRC: we generally use newrelic on irc.freenode.net
Find a bug? Contact us via support.newrelic.com, or email support@newrelic.com.
Thank you, and may your application scale to infinity plus one.
Lew Cirne, Founder and CEO
New Relic, Inc.