1 files changed, 25 insertions, 0 deletions
diff --git a/core/src/main/scala/org/apache/spark/deploy/master/MasterSource.scala b/core/src/main/scala/org/apache/spark/deploy/master/MasterSource.scala
new file mode 100644
index 0000000000..8dd0a42f71
--- /dev/null
+++ b/core/src/main/scala/org/apache/spark/deploy/master/MasterSource.scala
@@ -0,0 +1,25 @@
+package org.apache.spark.deploy.master
+
+import com.codahale.metrics.{Gauge, MetricRegistry}
+
+import org.apache.spark.metrics.source.Source
+
+private[spark] class MasterSource(val master: Master) extends Source {
+  val metricRegistry = new MetricRegistry()
+  val sourceName = "master"
+
+  // Gauge for worker numbers in cluster
+  metricRegistry.register(MetricRegistry.name("workers","number"), new Gauge[Int] {
+    override def getValue: Int = master.workers.size
+  })
+
+  // Gauge for application numbers in cluster
+  metricRegistry.register(MetricRegistry.name("apps", "number"), new Gauge[Int] {
+    override def getValue: Int = master.apps.size
+  })
+
+  // Gauge for waiting application numbers in cluster
+  metricRegistry.register(MetricRegistry.name("waitingApps", "number"), new Gauge[Int] {
+    override def getValue: Int = master.waitingApps.size
+  })
+}