A few months back Heroku introduced log-runtime-metrics, which you can enable to insert CPU load and memory usage metrics into your log events at 20 second intervals. Like all log data in it’s raw format it it’s not massively useful to see metrics getting dumped into your logs every 20 seconds. What if you want to look back at your performance over the past 20 mins, hour, or week for that matter, though? What if you want a real time view of total memory being used and not only average values? What if you want to correlate response time with spikes in resource consumption to figure out where your performance bottlenecks are coming from?