Hi Christian, I'm in the same boat as you and I've found its possible to use the sampleLabelValue query param I personally pass (RootProcessGroup|ProcessGroup) to it.
https://github.com/apache/nifi/blob/main/nifi-framework-bundle%2Fnifi-framework%2Fnifi-web%2Fnifi-web-api%2Fsrc%2Fmain%2Fjava%2Forg%2Fapache%2Fnifi%2Fweb%2Fapi%2FFlowResource.java#L576 The main drawback is it still iterates all the component metrics in the backend but at least your Prometheus will not need to store so much. I was thinking that the metrics endpoint should bring back the metrics reporting strategy as a query parameter that just applies to the NIFI metrics registry. -Eric On Mon, Jun 23, 2025, 3:24 AM Christian Wahl <[email protected]> wrote: > Hey guys, > > In NiFi 1.x I have used the PrometheusReportingTask and the Metrics > reporting strategy was set to "Root Process Group”. > > On 2.x I can fetch the data from the REST API endpoint > /nifi-api/flow/metrics/prometheus, but I can’t figure out how to restrict > it to only the Root Process Group like before. > Without any restrictions I get the metrics for every single component, > which is too much to handle (50-60k metrics). > > Has anyone an idea on how I can replicate the old behavior? > > Kind regards, > Christian Wahl
