Feature Request: Disable / filter custom micrometer metrics by name via OTEL Agent Config

[nenaraab]

Motivation

 
If instrumenting our SFPAY SpringBoot application with micrometer metrics it’s not possible to filter out custom metrics on a fine granular way via config.
This is only possible for non-custom metrics like jvm, tomcat, jdbc, hikaricp via application properties, e.g. management.metrics.enable.hikaricp=false.

Furthermore, we are now ingesting all micrometer metrics to CLS via otlp and openTelemetry Java Agent and here we also can't suppress some custom micrometer metrics via config (JVM parameters or environment variable).
 
Finally the otel-metrics-v1-* index gets flooded with the too many metrics and the promised retention period of 21 days is no longer guaranteed for observability purposes.

Proposal

JVM Parameters

-Dotel.instrumentation.micrometer.enabled=true|false
-Dotel.instrumentation.micrometer.disable.name=<comma-separated list of custom micrometer metric names>

Or (my favorite)

-Dotel.instrumentation.micrometer.enabled=true|false
-Dotel.instrumentation.micrometer.enabled.<custom micrometer metric name>=true|false

Example - Drop by Name

Given there is a metric

• name: sfpay.processtracker.atomicprocesses.accepted
• instrumentationScope.name: io.opentelemetry.micrometer-1.5

and given the below configuration, note that not the full name was configured:

-Dotel.instrumentation.micrometer.enabled=true
-Dotel.instrumentation.micrometer.enabled.sfpay.processtracker.atomicprocesses=false

Then the given metric should be dropped.

Related Requirement

In future there might be a requirement to not expose metrics for some dedicated attribute values but here I guess its always related to a dedicated metric. Hence, a key-value map would be required...

JVM Parameters

-Dotel.instrumentation.micrometer.enabled=true|false
-Dotel.instrumentation.micrometer.enabled.<custom micrometer metric name>={"<resource or metric attribute name>":"<resource or metric attribute value>", ...}

Example - Drop by Resource or Metric Attribute value

Given there is a metric

• name: sfpay.processtracker.atomicprocesses.accepted
• instrumentationScope.name: io.opentelemetry.micrometer-1.5
• metric.attributes.status: OK

and given the below configuration, note that not the full name was configured:

-Dotel.instrumentation.micrometer.enabled=true
-Dotel.instrumentation.micrometer.enabled.sfpay.processtracker.atomicprocesses={"metric.attributes.status":"ERROR"}

Then the given metric should be dropped.

References

• SpringBoot Doc - Metrics
  SAP-internal BTP Observability Support: How to a remove unwanted ingested metrics in CLS

[KarstenSchnitter]

Hi, thanks for submitting this proposal.

Your second link refers to an internal discussion at SAP. It helps me, but might not be useful for the public Github community.

The configuration -Dotel.instrumentation.micrometer.enabled=true is provided by the Micrometer auto-instrumentation of the OpenTelemetry Java Agent as documented here. If you want to introduce an instrumentation parameter to the Micrometer instrumentation like -Dotel.instrumentation.micrometer.disable.name, I can recommend reaching out to the opentelemetry-java-instrumenation project and create an issue there.

For the extension offered with this library, I can offer to add these configuration options.

Property	Remarks
otel.exporter.cloud-logging.metrics.include.names	A comma-separated list of metric names to export while rejecting all others.
otel.exporter.cloud-logging.metrics.exclude.names	A comma-separated list of metric names to reject while exporting all others.

This would allow you to define what metrics you would want to ship or which ones you would want. Would that work for your use-case? Would you need wildcard or prefix support for the filtering?

[nenaraab]

Hi @KarstenSchnitter,

wow- thanks a lot for your very fast response. I haven't even finished yet... Anyhow, we are using SAP Java Buildpack and the provisioned SAP OpenTelemetry Java Agent. Hence, I would appreciate your proposed JVM parameters to configure the exporter.

Would you need wildcard or prefix support for the filtering?

Yes. In case of JVM parameter otel.exporter.cloud-logging.metrics.exclude.names=namespace.a the metric with name namespace.a.b should be excluded.

Many Thanks!