1 files changed, 75 insertions, 0 deletions
diff --git a/kamon-system-metrics/src/main/scala/kamon/metrics/GCMetrics.scala b/kamon-system-metrics/src/main/scala/kamon/metrics/GCMetrics.scala
new file mode 100644
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+++ b/kamon-system-metrics/src/main/scala/kamon/metrics/GCMetrics.scala
@@ -0,0 +1,75 @@
+/*
+ * =========================================================================================
+ * Copyright © 2013-2014 the kamon project <http://kamon.io/>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ * =========================================================================================
+ */
+package kamon.metrics
+
+import java.lang.management.GarbageCollectorMXBean
+
+import akka.actor.ActorSystem
+import com.typesafe.config.Config
+import kamon.metric._
+import kamon.metric.instrument.{ Gauge, Histogram }
+
+case class GCMetrics(name: String) extends MetricGroupIdentity {
+  val category = GCMetrics
+}
+
+object GCMetrics extends MetricGroupCategory {
+  val name = "gc"
+
+  case object CollectionCount extends MetricIdentity { val name = "collection-count" }
+  case object CollectionTime extends MetricIdentity { val name = "collection-time" }
+
+  case class GCMetricRecorder(count: Gauge, time: Gauge)
+      extends MetricGroupRecorder {
+
+    def collect(context: CollectionContext): MetricGroupSnapshot = {
+      GCMetricSnapshot(count.collect(context), time.collect(context))
+    }
+
+    def cleanup: Unit = {}
+  }
+
+  case class GCMetricSnapshot(count: Histogram.Snapshot, time: Histogram.Snapshot)
+      extends MetricGroupSnapshot {
+
+    type GroupSnapshotType = GCMetricSnapshot
+
+    def merge(that: GroupSnapshotType, context: CollectionContext): GroupSnapshotType = {
+      GCMetricSnapshot(count.merge(that.count, context), time.merge(that.time, context))
+    }
+
+    lazy val metrics: Map[MetricIdentity, MetricSnapshot] = Map(
+      CollectionCount -> count,
+      CollectionTime -> time)
+  }
+
+  def Factory(gc: GarbageCollectorMXBean) = new MetricGroupFactory {
+
+    type GroupRecorder = GCMetricRecorder
+
+    def create(config: Config, system: ActorSystem): GroupRecorder = {
+      val settings = config.getConfig("precision.jvm.gc")
+
+      val countConfig = settings.getConfig("count")
+      val timeConfig = settings.getConfig("time")
+
+      new GCMetricRecorder(
+        Gauge.fromConfig(countConfig, system)(() ⇒ gc.getCollectionCount),
+        Gauge.fromConfig(timeConfig, system, Scale.Milli)(() ⇒ gc.getCollectionTime))
+    }
+  }
+}
+