Custom Metric Beacon allows every instance of ShowSlow to configure metrics it wants to record in addition to YSlow and PageSpeed ranking.
Once metric beacon is configured, simple GET/POST requests can be sent to the beacon with some numeric value which gets recorded and displayed over time on a graph.
You can also click on “Custom Metrics Beacon” on beacon list page (e.g. http://www.showslow.com/beacon/ for public instance) to see interactive form for manual submission.
Custom Metrics can vary depending on your needs, good examples include:
- bounce rate on the page (from your analytics software)
- amount of results on search page (from system configuration)
- server load (from backend monitoring tool)
All these metrics are specific to your needs and you have to write some tools to collect them, but ShowSlow will be able to aggregate them all along with the rest of the data.
For configuration docs, see Installation page on the wiki.