Revisit MP Metrics

[Emily-Jiang]

We need to revisit MP Metrics included in MicroProfile 6.0. MP Metrics should work closely with MP Telemetry team together with MP Fault Tolerance to evaluate the urgency to align with OTel Metrics.

#292

[kito99]

From a distance, the observability situation seems to be disjointed. It seems to me the best choice long term may be to just standardize on OpenTelemetry APIs across the board. Or come up with MP APIs as facades, but right now we have both.

[Emily-Jiang]

@kito99 we don't have both as OpenTelemetry Metrics has not been adopted by MicroProfile as yet. The plan is to either adopt OpenTelemetry Metrics APIs or making MP APIs as facades, which heads towards that way already.

[kito99]

@Emily-Jiang yes, I know. I guess what I'm saying is that it's strange that MP Metrics has its own API but MP Telemetry doesn't. Seems like they both should either have their own API or use OpenTelemetry.

[Emily-Jiang]

@kito99 good obeservation! The MP Telemetry uses the OpenTelemetry apis as OpenTelemetry under CNCF is a specification already. I think as for the metrics part, we can discuss further regarding our own Metrics API or adopt OpenTelemetry Metrics APIs.

[kito99]

👍🏾

[Emily-Jiang]

OpenTelemetry Metrics semantic convention is not stable as yet.