Ceph

as part of the strategy for sending more fine-grained metrics, we need the ability to add labels to the metrics we send

to take an example from rgw, we'd like the ability to send some per-bucket metrics. i think this means we want a single PerfCounter for "buckets", but whose individual metrics would use the bucket name as a label. that label would allow prometheus to filter by individual bucket, and to accumulate metrics over all buckets where necessary