OpenShift Serverless: Broker ingresses and filters showing error messages instead of metrics

Issue

• Broker ingresses and filters show messages like the ones below on port 9092 (:9292/metrics) instead of metrics.

• Ingress:

An error has occurred while serving metrics:
24 error(s) occurred:
* collected metric "mt_broker_ingress_event_count" { label:<name:"broker_name" value:"default" > label:<name:"container_name" value:"ingress" > label:<name:"event_type" value:"dev.knative.sources.ping" > label:<name:"namespace_name" value:"user1" > label:<name:"response_code" value:"202" > label:<name:"response_code_class" value:"2xx" > label:<name:"unique_name" value:"mt-broker-ingress-67ff9c869b-n88c8e5a848d2c97c277c43d81512e6cdf" > counter:<value:1 > } was collected before with the same name and label values
* collected metric "mt_broker_ingress_event_dispatch_latencies" { label:<name:"broker_name" value:"default" > label:<name:"container_name" value:"ingress" > label:<name:"event_type" value:"dev.knative.sources.ping" > label:<name:"namespace_name" value:"user1" > label:<name:"response_code" value:"202" > label:<name:"response_code_class" value:"2xx" > label:<name:"unique_name" value:"mt-broker-ingress-67ff9c869b-n88c8e5a848d2c97c277c43d81512e6cdf" > histogram:<sample_count:1 sample_sum:28 bucket:<cumulative_count:0 upper_bound:1 > bucket:<cumulative_count:0 upper_bound:2 > bucket:<cumulative_count:0 upper_bound:5 > bucket:<cumulative_count:0 upper_bound:10 > bucket:<cumulative_count:0 upper_bound:20 > bucket:<cumulative_count:1 upper_bound:50 > bucket:<cumulative_count:1 upper_bound:100 > bucket:<cumulative_count:1 upper_bound:200 > bucket:<cumulative_count:1 upper_bound:500 > bucket:<cumulative_count:1 upper_bound:1000 > bucket:<cumulative_count:1 upper_bound:2000 > bucket:<cumulative_count:1 upper_bound:5000 > bucket:<cumulative_count:1 upper_bound:10000 > > } was collected before with the same name and label values
* collected metric "mt_broker_ingress_event_count" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"ingress" > label:<name:"event_type" value:"dev.knative.sources.ping" > label:<name:"namespace_name" value:"user2" > label:<name:"response_code" value:"202" > label:<name:"response_code_class" value:"2xx" > label:<name:"unique_name" value:"mt-broker-ingress-67ff9c869b-n88c8e5a848d2c97c277c43d81512e6cdf" > counter:<value:3 > } was collected before with the same name and label values
* collected metric "mt_broker_ingress_event_dispatch_latencies" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"ingress" > label:<name:"event_type" value:"dev.knative.sources.ping" > label:<name:"namespace_name" value:"user2" > label:<name:"response_code" value:"202" > label:<name:"response_code_class" value:"2xx" > label:<name:"unique_name" value:"mt-broker-ingress-67ff9c869b-n88c8e5a848d2c97c277c43d81512e6cdf" > histogram:<sample_count:3 sample_sum:16231.000000000002 bucket:<cumulative_count:0 upper_bound:1 > bucket:<cumulative_count:0 upper_bound:2 > bucket:<cumulative_count:0 upper_bound:5 > bucket:<cumulative_count:0 upper_bound:10 > bucket:<cumulative_count:0 upper_bound:20 > bucket:<cumulative_count:1 upper_bound:50 > bucket:<cumulative_count:1 upper_bound:100 > bucket:<cumulative_count:1 upper_bound:200 > bucket:<cumulative_count:1 upper_bound:500 > bucket:<cumulative_count:1 upper_bound:1000 > bucket:<cumulative_count:1 upper_bound:2000 > bucket:<cumulative_count:2 upper_bound:5000 > bucket:<cumulative_count:2 upper_bound:10000 > > } was collected before with the same name and label values

• Filter:

An error has occurred while serving metrics:

104 error(s) occurred:
* collected metric "mt_broker_filter_event_count" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user1" > label:<name:"response_code" value:"200" > label:<name:"response_code_class" value:"2xx" > label:<name:"trigger_name" value:"sockeye" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > counter:<value:17 > } was collected before with the same name and label values
* collected metric "mt_broker_filter_event_dispatch_latencies" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user1" > label:<name:"response_code" value:"200" > label:<name:"response_code_class" value:"2xx" > label:<name:"trigger_name" value:"sockeye" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > histogram:<sample_count:17 sample_sum:134 bucket:<cumulative_count:0 upper_bound:1 > bucket:<cumulative_count:0 upper_bound:2 > bucket:<cumulative_count:9 upper_bound:5 > bucket:<cumulative_count:13 upper_bound:10 > bucket:<cumulative_count:15 upper_bound:20 > bucket:<cumulative_count:17 upper_bound:50 > bucket:<cumulative_count:17 upper_bound:100 > bucket:<cumulative_count:17 upper_bound:200 > bucket:<cumulative_count:17 upper_bound:500 > bucket:<cumulative_count:17 upper_bound:1000 > bucket:<cumulative_count:17 upper_bound:2000 > bucket:<cumulative_count:17 upper_bound:5000 > bucket:<cumulative_count:17 upper_bound:10000 > > } was collected before with the same name and label values
* collected metric "mt_broker_filter_event_processing_latencies" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user1" > label:<name:"trigger_name" value:"sockeye" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > histogram:<sample_count:17 sample_sum:75 bucket:<cumulative_count:10 upper_bound:1 > bucket:<cumulative_count:10 upper_bound:2 > bucket:<cumulative_count:10 upper_bound:5 > bucket:<cumulative_count:12 upper_bound:10 > bucket:<cumulative_count:16 upper_bound:20 > bucket:<cumulative_count:17 upper_bound:50 > bucket:<cumulative_count:17 upper_bound:100 > bucket:<cumulative_count:17 upper_bound:200 > bucket:<cumulative_count:17 upper_bound:500 > bucket:<cumulative_count:17 upper_bound:1000 > bucket:<cumulative_count:17 upper_bound:2000 > bucket:<cumulative_count:17 upper_bound:5000 > bucket:<cumulative_count:17 upper_bound:10000 > > } was collected before with the same name and label values
* collected metric "mt_broker_filter_event_processing_latencies" { label:<name:"broker_name" value:"default" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user2" > label:<name:"trigger_name" value:"go-lambda-trigger" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > histogram:<sample_count:2 sample_sum:13 bucket:<cumulative_count:1 upper_bound:1 > bucket:<cumulative_count:1 upper_bound:2 > bucket:<cumulative_count:1 upper_bound:5 > bucket:<cumulative_count:1 upper_bound:10 > bucket:<cumulative_count:2 upper_bound:20 > bucket:<cumulative_count:2 upper_bound:50 > bucket:<cumulative_count:2 upper_bound:100 > bucket:<cumulative_count:2 upper_bound:200 > bucket:<cumulative_count:2 upper_bound:500 > bucket:<cumulative_count:2 upper_bound:1000 > bucket:<cumulative_count:2 upper_bound:2000 > bucket:<cumulative_count:2 upper_bound:5000 > bucket:<cumulative_count:2 upper_bound:10000 > > } was collected before with the same name and label values
* collected metric "mt_broker_filter_event_count" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user3" > label:<name:"response_code" value:"502" > label:<name:"response_code_class" value:"5xx" > label:<name:"trigger_name" value:"tekton" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > counter:<value:4 > } was collected before with the same name and label values
* collected metric "mt_broker_filter_event_dispatch_latencies" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user3" > label:<name:"response_code" value:"502" > label:<name:"response_code_class" value:"5xx" > label:<name:"trigger_name" value:"tekton" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > histogram:<sample_count:4 sample_sum:130 bucket:<cumulative_count:0 upper_bound:1 > bucket:<cumulative_count:0 upper_bound:2 > bucket:<cumulative_count:0 upper_bound:5 > bucket:<cumulative_count:0 upper_bound:10 > bucket:<cumulative_count:0 upper_bound:20 > bucket:<cumulative_count:4 upper_bound:50 > bucket:<cumulative_count:4 upper_bound:100 > bucket:<cumulative_count:4 upper_bound:200 > bucket:<cumulative_count:4 upper_bound:500 > bucket:<cumulative_count:4 upper_bound:1000 > bucket:<cumulative_count:4 upper_bound:2000 > bucket:<cumulative_count:4 upper_bound:5000 > bucket:<cumulative_count:4 upper_bound:10000 > > } was collected before with the same name and label values
* collected metric "mt_broker_filter_event_processing_latencies" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user3" > label:<name:"trigger_name" value:"tekton" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > histogram:<sample_count:4 sample_sum:47.99999999999999 bucket:<cumulative_count:2 upper_bound:1 > bucket:<cumulative_count:2 upper_bound:2 > bucket:<cumulative_count:3 upper_bound:5 > bucket:<cumulative_count:3 upper_bound:10 > bucket:<cumulative_count:3 upper_bound:20 > bucket:<cumulative_count:4 upper_bound:50 > bucket:<cumulative_count:4 upper_bound:100 > bucket:<cumulative_count:4 upper_bound:200 > bucket:<cumulative_count:4 upper_bound:500 > bucket:<cumulative_count:4 upper_bound:1000 > bucket:<cumulative_count:4 upper_bound:2000 > bucket:<cumulative_count:4 upper_bound:5000 > bucket:<cumulative_count:4 upper_bound:10000 > > } was collected before with the same name and label values
* collected metric "mt_broker_filter_event_count" { label:<name:"broker_name" value:"events" > label:<name:"container_name" value:"filter" > label:<name:"filter_type" value:"any" > label:<name:"namespace_name" value:"user3" > label:<name:"response_code" value:"502" > label:<name:"response_code_class" value:"5xx" > label:<name:"trigger_name" value:"tekton" > label:<name:"unique_name" value:"mt-broker-filter-56964c97dd-5d5ce54f1b5276f60c0a4ee8462d7f216b7" > counter:<value:1 > } was collected before with the same name and label values