For almost two years now, the Heroku Dashboard has provided a metrics page to display information about memory usage and CPU load for all of the dynos running an application. Additionally, we've been providing aggregate error metrics, as well as metrics from the Heroku router about incoming requests: average and P95 response time, counts by status, etc.
Almost all of this information is being slurped out of an application's log stream via the Log Runtime Metrics labs feature. For applications that don't have this flag enabled, which is most applications on the platform, the relevant logs are still generated, but bypass Logplex, and are instead sent directly to our metrics...