Every node writes a sample per metric on metricsCollectionInterval:
counters as the increase since its last sample, gauges always, histograms
as totals when changed. Samples are x:Metric in the registry's encoding
under the telemetry key class, ids time-ordered. x:Metric/get and /query
read them with metric and timestamp filters and full paging, hide what's
past holdMetricsFor, and the data purge deletes it. The is_enterprise
split is gone, so every gauge and histogram is collected and exported, and
queue.count is set from the queue itself. The shared metrics suite runs.
jcoffey-dev
9f7035588f