See #15777 (comment)

Use Cases

Use cases to disable a module:

• agent: problems inherent in using bytecode instrumentation
• native instrumentation: comment from @trask I'm not sure that's an important use case outside of the Java agent (which needs it due to it being zero code, and due to the problems inherent in using bytecode instrumentation)
• spring starter: does not have bytecode, but startup time is important - and users expect to be able to disable modules

What else can be done:

• Tracer can be disabled in declarative config: https://github.com/open-telemetry/opentelemetry-configuration/blob/main/snippets/ExperimentalTracerConfigurator_kitchen_sink.yaml
• same for logger: https://github.com/open-telemetry/opentelemetry-configuration/blob/main/snippets/ExperimentalLoggerConfigurator_kitchen_sink.yaml
• and meter: https://github.com/open-telemetry/opentelemetry-configuration/blob/main/snippets/ExperimentalMeterConfigurator_kitchen_sink.yaml

Design

Note:

• this issue includes the task to move all "javaagent" properties to the distribution node (Declarative configuration: move .instrumentation.java.agent node to .distribution.java_agent #15800)

Agent

distribution:
  javaagent:
    instrumentation:
      default_enabled: true
      disabled:
        - dropwizard
      enabled: # used if default_enabled=false
        - dropwizard

Spring Starter

same, but use spring_starter as distro name.

Native Instrumentation

It might also be good to give native instrumentations the ability to no-op quickly, but they can already tracer/instrument/logger isEnabled and we want to see if that is sufficient.