align naming with opentelemetry semantic conventions

Author: gniadeck

prometheus-metrics-instrumentation-jvm/src/main/java/io/prometheus/metrics/instrumentation/jvm/JvmGarbageCollectorMetrics.java

@@ -43,7 +43,7 @@
 public class JvmGarbageCollectorMetrics {
 
   private static final String JVM_GC_COLLECTION_SECONDS = "jvm_gc_collection_seconds";
-  private static final String JVM_GC_DURATION_SECONDS = "jvm_gc_duration_seconds";
+  private static final String JVM_GC_DURATION = "jvm_gc_duration";
 
   private final PrometheusProperties config;
   private final List<GarbageCollectorMXBean> garbageCollectorBeans;
@@ -81,10 +81,9 @@ private void registerGCDurationHistogram(PrometheusRegistry registry) {
 
     Histogram gcDurationHistogram =
         Histogram.builder(config)
-            .name(JVM_GC_DURATION_SECONDS)
-            .help("JVM GC pause duration histogram.")
-            .unit(Unit.SECONDS)
-            .labelNames("name", "action", "cause")
+            .name(JVM_GC_DURATION)
+            .help("Duration of JVM garbage collection actions.")
+            .labelNames("jvm_gc_action", "jvm_gc_name", "jvm_gc_cause")
             .classicUpperBounds(buckets)
             .register(registry);
 
@@ -107,7 +106,7 @@ private void registerGCDurationHistogram(PrometheusRegistry registry) {
                         (CompositeData) notification.getUserData());
 
                 gcDurationHistogram
-                    .labelValues(info.getGcName(), info.getGcAction(), info.getGcCause())
+                    .labelValues(info.getGcAction(), info.getGcName(), info.getGcCause())
                     .observe(Unit.millisToSeconds(info.getGcInfo().getDuration()));
               },
               null,

prometheus-metrics-instrumentation-jvm/src/test/java/io/prometheus/metrics/instrumentation/jvm/JvmGarbageCollectorMetricsTest.java

@@ -59,7 +59,7 @@ public void testGoodCase() throws IOException {
   public void testIgnoredMetricNotScraped() {
     MetricNameFilter filter =
         MetricNameFilter.builder()
-            .nameMustNotBeEqualTo("jvm_gc_collection_seconds", "jvm_gc_duration_seconds")
+            .nameMustNotBeEqualTo("jvm_gc_collection_seconds", "jvm_gc_duration")
             .build();
 
     PrometheusRegistry registry = new PrometheusRegistry();