Breaking change: disable micrometer bridge by default (#10038)

instrumentation/micrometer/micrometer-1.5/javaagent/build.gradle.kts

@@ -57,4 +57,8 @@ tasks {
     dependsOn(testPrometheusMode)
     dependsOn(testHistogramGauges)
   }
+
+  withType<Test>().configureEach {
+    jvmArgs("-Dotel.instrumentation.micrometer.enabled=true")
+  }
 }

instrumentation/micrometer/micrometer-1.5/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/micrometer/v1_5/MicrometerInstrumentationModule.java

@@ -10,6 +10,7 @@ import static io.opentelemetry.javaagent.extension.matcher.AgentElementMatchers.
 import com.google.auto.service.AutoService;
 import io.opentelemetry.javaagent.extension.instrumentation.InstrumentationModule;
 import io.opentelemetry.javaagent.extension.instrumentation.TypeInstrumentation;
+import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
 import java.util.Collections;
 import java.util.List;
 import net.bytebuddy.matcher.ElementMatcher;
@@ -21,6 +22,12 @@ public class MicrometerInstrumentationModule extends InstrumentationModule {
     super("micrometer", "micrometer-1.5");
   }
 
+  @Override
+  public boolean defaultEnabled(ConfigProperties config) {
+    // produces a lot of metrics that are already captured - e.g. JVM memory usage
+    return false;
+  }
+
   @Override
   public ElementMatcher.Junction<ClassLoader> classLoaderMatcher() {
     // added in 1.5

instrumentation/spring/spring-boot-autoconfigure/src/main/java/io/opentelemetry/instrumentation/spring/autoconfigure/instrumentation/micrometer/MicrometerBridgeAutoConfiguration.java

@@ -23,7 +23,7 @@ import org.springframework.context.annotation.Configuration;
 @AutoConfigureBefore(CompositeMeterRegistryAutoConfiguration.class)
 @ConditionalOnBean({Clock.class, OpenTelemetry.class})
 @ConditionalOnClass(MeterRegistry.class)
-@ConditionalOnProperty(name = "otel.instrumentation.micrometer.enabled", matchIfMissing = true)
+@ConditionalOnProperty(name = "otel.instrumentation.micrometer.enabled")
 @Configuration
 public class MicrometerBridgeAutoConfiguration {
 

instrumentation/spring/spring-boot-autoconfigure/src/test/java/io/opentelemetry/instrumentation/spring/autoconfigure/instrumentation/micrometer/MicrometerBridgeAutoConfigurationTest.java

@@ -35,14 +35,10 @@ class MicrometerBridgeAutoConfigurationTest {
   }
 
   @Test
-  void metricsEnabledByDefault() {
+  void metricsDisabledByDefault() {
     runner
         .withConfiguration(AutoConfigurations.of(MetricsAutoConfiguration.class))
-        .run(
+        .run(context -> assertThat(context.containsBean("otelMeterRegistry")).isFalse());
-            context ->
-                assertThat(context.getBean("otelMeterRegistry", MeterRegistry.class))
-                    .isNotNull()
-                    .isInstanceOf(OpenTelemetryMeterRegistry.class));
   }
 
   @Test