1 files changed, 96 insertions, 0 deletions
diff --git a/kamon-system-metrics/src/main/scala/kamon/metrics/MemoryMetrics.scala b/kamon-system-metrics/src/main/scala/kamon/metrics/MemoryMetrics.scala
new file mode 100644
index 00000000..4f6cb1cd
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+++ b/kamon-system-metrics/src/main/scala/kamon/metrics/MemoryMetrics.scala
@@ -0,0 +1,96 @@
+/*
+ * =========================================================================================
+ * 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 akka.actor.ActorSystem
+import com.typesafe.config.Config
+import kamon.metric._
+import kamon.metric.instrument.Gauge.CurrentValueCollector
+import kamon.metric.instrument.{ Gauge, Histogram }
+import kamon.system.SigarExtensionProvider
+import org.hyperic.sigar.Mem
+
+case class MemoryMetrics(name: String) extends MetricGroupIdentity {
+  val category = MemoryMetrics
+}
+
+object MemoryMetrics extends MetricGroupCategory {
+  val name = "memory"
+
+  case object Used extends MetricIdentity { val name = "used" }
+  case object Free extends MetricIdentity { val name = "free" }
+  case object Buffer extends MetricIdentity { val name = "buffer" }
+  case object Cache extends MetricIdentity { val name = "cache" }
+  case object SwapUsed extends MetricIdentity { val name = "swap-used" }
+  case object SwapFree extends MetricIdentity { val name = "swap-free" }
+
+  case class MemoryMetricRecorder(used: Gauge, free: Gauge, buffer: Gauge, cache: Gauge, swapUsed: Gauge, swapFree: Gauge)
+      extends MetricGroupRecorder {
+
+    def collect(context: CollectionContext): MetricGroupSnapshot = {
+      MemoryMetricSnapshot(used.collect(context), free.collect(context), buffer.collect(context), cache.collect(context), swapUsed.collect(context), swapFree.collect(context))
+    }
+
+    def cleanup: Unit = {}
+  }
+
+  case class MemoryMetricSnapshot(used: Histogram.Snapshot, free: Histogram.Snapshot, buffer: Histogram.Snapshot, cache: Histogram.Snapshot, swapUsed: Histogram.Snapshot, swapFree: Histogram.Snapshot)
+      extends MetricGroupSnapshot {
+
+    type GroupSnapshotType = MemoryMetricSnapshot
+
+    def merge(that: GroupSnapshotType, context: CollectionContext): GroupSnapshotType = {
+      MemoryMetricSnapshot(used.merge(that.used, context), free.merge(that.free, context), buffer.merge(that.buffer, context), cache.merge(that.cache, context), swapUsed.merge(that.swapUsed, context), swapFree.merge(that.swapFree, context))
+    }
+
+    lazy val metrics: Map[MetricIdentity, MetricSnapshot] = Map(
+      Used -> used,
+      Free -> free,
+      Buffer -> buffer,
+      Cache -> cache,
+      SwapUsed -> swapUsed,
+      SwapFree -> swapFree)
+  }
+
+  val Factory = new MetricGroupFactory with SigarExtensionProvider {
+    def mem = sigar.getMem
+    def swap = sigar.getSwap
+
+    type GroupRecorder = MemoryMetricRecorder
+
+    def create(config: Config, system: ActorSystem): GroupRecorder = {
+      val settings = config.getConfig("precision.system.memory")
+
+      val usedConfig = settings.getConfig("used")
+      val freeConfig = settings.getConfig("free")
+      val bufferConfig = settings.getConfig("buffer")
+      val cacheConfig = settings.getConfig("cache")
+      val swapUsedConfig = settings.getConfig("swap-used")
+      val swapFreeConfig = settings.getConfig("swap-free")
+
+      new MemoryMetricRecorder(
+        Gauge.fromConfig(usedConfig, system)(() ⇒ mem.getUsed),
+        Gauge.fromConfig(freeConfig, system)(() ⇒ mem.getFree),
+        Gauge.fromConfig(bufferConfig, system)(() ⇒ swap.getUsed),
+        Gauge.fromConfig(cacheConfig, system)(() ⇒ swap.getFree),
+        Gauge.fromConfig(swapUsedConfig, system)(collectBuffer(mem)),
+        Gauge.fromConfig(swapFreeConfig, system)(collectCache(mem)))
+    }
+
+    private def collectBuffer(mem: Mem) = () ⇒ if (mem.getUsed() != mem.getActualUsed()) mem.getActualUsed() else 0L
+    private def collectCache(mem: Mem) = () ⇒ if (mem.getFree() != mem.getActualFree()) mem.getActualFree() else 0L
+  }
+}
+\ No newline at end of file