New Relic RPM is a Ruby performance management system, developed by New Relic, Inc (http://www.newrelic.com). RPM provides you with deep information about the performance of your Ruby on Rails or Merb application as it runs in production. The New Relic Agent is dual-purposed as a either a Rails plugin or a Gem, hosted on http://github.com/newrelic/rpm/tree/master.
Gemfile gem 'newrelic_rpm', '~> 2.12.2.beta'
install gem install newrelic_rpm -v 2.12.2.beta --pre