Specify ...jvm.gc.duration buckets using advice API

open-telemetry · May 15, 2023 · 02c8d9e · 02c8d9e
1 parent c660a80
commit 02c8d9e
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Showing 3 changed files with 35 additions and 16 deletions.
diff --git a/instrumentation/runtime-metrics/library/build.gradle.kts b/instrumentation/runtime-metrics/library/build.gradle.kts
@@ -4,6 +4,7 @@ plugins {
 
 dependencies {
  implementation(project(":instrumentation-api"))
+ implementation("io.opentelemetry:opentelemetry-extension-incubator")
 
  testImplementation("io.opentelemetry:opentelemetry-sdk-metrics")
  testImplementation(project(":testing-common"))

diff --git a/...brary/src/main/java/io/opentelemetry/instrumentation/runtimemetrics/GarbageCollector.java b/...brary/src/main/java/io/opentelemetry/instrumentation/runtimemetrics/GarbageCollector.java
@@ -5,15 +5,20 @@
 
 package io.opentelemetry.instrumentation.runtimemetrics;
 
+import static java.util.Collections.emptyList;
+
 import com.sun.management.GarbageCollectionNotificationInfo;
 import io.opentelemetry.api.OpenTelemetry;
 import io.opentelemetry.api.common.AttributeKey;
 import io.opentelemetry.api.common.Attributes;
-import io.opentelemetry.api.metrics.LongHistogram;
+import io.opentelemetry.api.metrics.DoubleHistogram;
+import io.opentelemetry.api.metrics.DoubleHistogramBuilder;
 import io.opentelemetry.api.metrics.Meter;
+import io.opentelemetry.extension.incubator.metrics.ExtendedDoubleHistogramBuilder;
 import java.lang.management.GarbageCollectorMXBean;
 import java.lang.management.ManagementFactory;
 import java.util.List;
+import java.util.concurrent.TimeUnit;
 import java.util.function.Function;
 import java.util.logging.Logger;
 import javax.management.Notification;
@@ -35,6 +40,8 @@ public final class GarbageCollector {
 
  private static final Logger logger = Logger.getLogger(GarbageCollector.class.getName());
 
+ private static final double MILLIS_PER_S = TimeUnit.SECONDS.toMillis(1);
+
  private static final AttributeKey<String> GC_KEY = AttributeKey.stringKey("gc");
  private static final AttributeKey<String> ACTION_KEY = AttributeKey.stringKey("action");
 
@@ -66,43 +73,52 @@ static void registerObservers(
  Function<Notification, GarbageCollectionNotificationInfo> notificationInfoExtractor) {
  Meter meter = RuntimeMetricsUtil.getMeter(openTelemetry);
 
- LongHistogram gcTime =
+ DoubleHistogramBuilder gcDurationBuilder =
  meter
  .histogramBuilder("process.runtime.jvm.gc.duration")
  .setDescription("Duration of JVM garbage collection actions")
- .setUnit("ms")
-  .ofLongs()
-  .build();
+ .setUnit("s");
+ setGcDurationBuckets(gcDurationBuilder);
+ DoubleHistogram gcDuration = gcDurationBuilder.build();
 
  for (GarbageCollectorMXBean gcBean : gcBeans) {
  if (!(gcBean instanceof NotificationEmitter)) {
  continue;
  }
  NotificationEmitter notificationEmitter = (NotificationEmitter) gcBean;
  notificationEmitter.addNotificationListener(
- new GcNotificationListener(gcTime, notificationInfoExtractor), GC_FILTER, null);
+ new GcNotificationListener(gcDuration, notificationInfoExtractor), GC_FILTER, null);
+ }
+ }
+
+ private static void setGcDurationBuckets(DoubleHistogramBuilder builder) {
+ if (!(builder instanceof ExtendedDoubleHistogramBuilder)) {
+ // that shouldn't really happen
+ return;
  }
+ ((ExtendedDoubleHistogramBuilder) builder)
+ .setAdvice(advice -> advice.setExplicitBucketBoundaries(emptyList()));
  }
 
  private static final class GcNotificationListener implements NotificationListener {
 
- private final LongHistogram gcTime;
+ private final DoubleHistogram gcDuration;
  private final Function<Notification, GarbageCollectionNotificationInfo>
  notificationInfoExtractor;
 
  private GcNotificationListener(
- LongHistogram gcTime,
+ DoubleHistogram gcDuration,
  Function<Notification, GarbageCollectionNotificationInfo> notificationInfoExtractor) {
- this.gcTime = gcTime;
+ this.gcDuration = gcDuration;
  this.notificationInfoExtractor = notificationInfoExtractor;
  }
 
  @Override
  public void handleNotification(Notification notification, Object unused) {
  GarbageCollectionNotificationInfo notificationInfo =
  notificationInfoExtractor.apply(notification);
- gcTime.record(
- notificationInfo.getGcInfo().getDuration(),
+ gcDuration.record(
+ notificationInfo.getGcInfo().getDuration() / MILLIS_PER_S,
  Attributes.of(
  GC_KEY, notificationInfo.getGcName(), ACTION_KEY, notificationInfo.getGcAction()));
  }

diff --git a/...y/src/test/java/io/opentelemetry/instrumentation/runtimemetrics/GarbageCollectorTest.java b/...y/src/test/java/io/opentelemetry/instrumentation/runtimemetrics/GarbageCollectorTest.java
@@ -72,28 +72,30 @@ void registerObservers() {
  assertThat(metricData)
  .hasInstrumentationScope(EXPECTED_SCOPE)
  .hasDescription("Duration of JVM garbage collection actions")
- .hasUnit("ms")
+ .hasUnit("s")
  .hasHistogramSatisfying(
  histogram ->
  histogram.hasPointsSatisfying(
  point ->
  point
  .hasCount(2)
- .hasSum(22)
+ .hasSum(0.022)
  .hasAttributes(
  Attributes.builder()
  .put("gc", "G1 Young Generation")
  .put("action", "end of minor GC")
- .build()),
+ .build())
+ .hasBucketBoundaries(),
  point ->
  point
  .hasCount(1)
- .hasSum(11)
+ .hasSum(0.011)
  .hasAttributes(
  Attributes.builder()
  .put("gc", "G1 Old Generation")
  .put("action", "end of major GC")
- .build())))));
+ .build())
+ .hasBucketBoundaries()))));
  }
 
  private static Notification createTestNotification(