> > This kind of change will be problematic to us as the total RequestsPerSec > will be double counted in our metric system as we do automatic aggregation. > It has been a headache for us as we always have to do some special handling > when querying such metrics. >
I agree with Allen, most of the metrics are already setup to be aggregated across the various tags dimensions. We do the same on with our metrics, and any respectable metrics system would allow you to do the same. It sounds like backwards compatibility in this case is more subjective, since it depends largely on how you consume / aggregate those metrics, but in my opinion, aggregation should be the way to go. There is precedent with topic based metrics such as BytesInPerSec, which are currently duplicated, once at the broker level (no topic tag), and once at the topic level (tagged with the topic name) and it's easy to miss that fact. Without looking the source code it's very hard to notice those subtleties. As a result it can be very error-prone to filter out the right metrics for aggregation, so I would argue we should not repeat the same mistake unless we had some good reasons to do so in the first place.
