Native Heroku Metrics
Router metrics are present in every Heroku application log stream and provide detailed information (including timing) about every request serviced by your application. Librato calculates a rich set of summary statistics (described below in custom distributions) including median, 90th percentile, and 99th percentile latency that provide unprecedented insight into your application's performance.
Postgres metrics are present in the log stream of any Heroku application with a provisioned Heroku Postgres database. These metrics are summary statistics gathered by the Heroku Postgres service and are reported directly into Librato under their given names.
Per-dyno runtime metrics are available to any Heroku application, but must be enabled by the user. They provide insight into both memory usage and CPU load of each dyno and are reported under the dyno's logical role e.g. web.1 or worker.2.
Perhaps even more exciting, you can use the same logs integration to submit any custom metrics through a simple, intuitive, logging format. If your application can write to standard out (stdout), than you can report custom metrics and have access to powerful statistical aggregations like distributed counting and percentiles. And you still have complete access to our RESTful API and the growing list of OSS/third-party integrations provided by our burgeoning community.
New Pricing Plans
We've also simplified our add-on plans into a simple progression with increasingly larger capacity for metrics. Our development plan is free and includes a single dashboard that details native router and postgres metrics, including your application's median and 99th percentile response times. To gain access to per-dyno system resource metrics and/or custom metrics you can easily upgrade to whichever one of our paid plans best fits your usage.