New Relic Blog

Rails 3 is here! This is a major milestone for the Rails community. We’ve been working closely with the Rails core team on increasingly better instrumentation and we’re beyond thrilled to see the final release go live!

We want to especially thank Yehuda Katz, Jeremy Kemper and Carl Lerche for all their support during this release. We caught up with Yehuda earlier this year at RailsConf to talk about what’s new in Rails 3. Check out the video here.

We are really excited about all the improvements that Rails 3 offers. Everyone benefits greatly from all the work invested in making Rails not only more extensible but also more performant and easier to instrument, providing even greater opportunity to improve the stability and performance of our Rails applications.

RPM on Rails 3: Getting Started

The RPM Ruby Agent gem (newrelic_rpm) version 2.13.0.beta5, supports Rails 3. We will be pushing a newer version soon to include the most recent changes to Rails 3, including even better support for the ActiveSupport::Notification framework.

To include RPM in your Rails project, add the following line to your Gemfile:
gem 'newrelic_rpm', '2.13.0.beta5'

Starting with Rails 3, we’re recommending using the gem distribution instead of the plugin. As you may know, Bundler is a new and important component in the Ruby ecosystem, and was designed to manage your applications’ dependencies.

Differences in RPM with Rails 3

Our aim is to ensure all the features of RPM continue to work as expected with Rails 3. A byproduct of the new architecture of Rails 3 is that your stack traces will likely be cleaner and easier to read. The creation of Active Relation and Active Model in Rails 3 also changes the way Rails handles database queries. Using RPM, you’ll be able to see how these changes effect your application through database analysis as well as within the context of a given controller action.

As always, if you have any questions please send an email at support@newrelic.com, post a note on our support site or hit us up on on twitter @newrelic or on IRC in #newrelic on freenode.

So get out there and enjoy Rails 3 with great instrumentation! We’ll be looking for Rails 3 to get major traction by the next State of the Stack report!