What problem are you facing?

Crossplane users would benefit from the ability to offer service level objectives (SLOs) to their users. To do this they need MR related metrics.

How could Crossplane help solve your problem?

At the Crossplane pod port 8080/metrics interface, expose the following:

• number of MRs total, by claim, by composition

• number of MRs in Synched False State total, by claim, by composition

• number of MRs in Synched True State total, by claim, by composition

• number of MRs in Synched Unkown State total, by claim, by composition

• number of MRs in Ready False State total, by claim, by composition

• number of MRs in Ready True State total, by claim, by composition

• number of MRs in Ready Unknown State total, by claim, by composition

• number of MRs in Synched True and Ready True State total, by claim, by composition

• number of MRs in Synched False and Ready True State total, by claim, by composition

• number of MRs in Synched Unknown and Ready True State total, by claim, by composition

• number of MRs in Synched True and Ready False State total, by claim, by composition

• number of MRs in Synched False and Ready False State total, by claim, by composition

• number of MRs in Synched Unknown and Ready False State total, by claim, by composition

• for each MR, time to readiness (Synched True -> Ready True)

• for each MR, time to non-readiness (Ready True -> Synched !True)

• for each MR, number of Synched state changes

• for each MR, number of Ready state changes

• for each MR, time from deletion request to external resource and MR deletion

• for each claim, time to readiness (from claim created to ready)

• for each claim, time to delete all associated resources (from claim to external resources removed)

• if possible, control plane availability and uptime (since last Crossplane pod restart).

The implementation of the metric gathering could be performed in the Crossplane runtime reconciler code, line 675+.
https://github.com/crossplane/crossplane-runtime/blob/master/pkg/reconciler/managed/reconciler.go#L675

An example time to readiness calculation is located in Uptest at https://github.com/upbound/uptest/blob/6e567ebd9ed30f1b1670d2cbbb679fde9beebc6b/cmd/perf/internal/managed/managed.go#L171