Ganglia metrics

OSC recently developed some Open OnDemand metric views using Ganglia which show us near real time the number of clients using OOD at OSC, as well as the number of apps (PUNs) in use and live interactive sessions. Attached is an example screenshot. We’d be happy to share the details of how we did this with anyone interested in implementing at their site.

I have published the Ganglia plugin here: https://github.com/OSC/ondemand-metrics/tree/master/ganglia

Worth noting there is a behavior change with what a process from Passenger looks like for Rack apps so the code in ondemand-metrics is intended to work with upcoming OnDemand 1.4 release that uses Passenger 5. If this is used with OnDemand 1.3 the ood_rack_apps metric will always be 0.