YARN-10702. Add cluster metric for amount of CPU used by RM Event Processor.

Contributed by Jim Brennan.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java

@@ -2903,6 +2903,18 @@ public class YarnConfiguration extends Configuration {
   public static final int
           DEFAULT_YARN_DISPATCHER_PRINT_EVENTS_INFO_THRESHOLD = 5000;
 
+  /** Resource manager dispatcher thread monitor sampling rate.
+   * Units are samples per minute.  This controls how often to sample
+   * the cpu utilization of the resource manager dispatcher thread.
+   * The cpu utilization is displayed on the RM UI as scheduler busy %.
+   * Set to zero to disable the dispatcher thread monitor.
+   */
+  public static final String
+      YARN_DISPATCHER_CPU_MONITOR_SAMPLES_PER_MIN =
+      YARN_PREFIX + "dispatcher.cpu-monitor.samples-per-min";
+  public static final int
+      DEFAULT_YARN_DISPATCHER_CPU_MONITOR_SAMPLES_PER_MIN = 60;
+
   /**
    * CLASSPATH for YARN applications. A comma-separated list of CLASSPATH
    * entries

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/event/EventDispatcher.java

@@ -136,4 +136,11 @@ public class EventDispatcher<T extends Event> extends
   public void disableExitOnError() {
     shouldExitOnError = false;
   }
+  protected long getEventProcessorId() {
+    return this.eventProcessor.getId();
+  }
+
+  protected boolean isStopped() {
+    return this.stopped;
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/resources/yarn-default.xml

@@ -120,6 +120,19 @@
     <value>5000</value>
   </property>
 
+  <property>
+    <description>
+      Resource manager dispatcher thread cpu monitor sampling rate.
+      Units are samples per minute.  This controls how often to sample
+      the cpu utilization of the resource manager dispatcher thread.
+      The cpu utilization is displayed on the RM UI as scheduler busy %.
+      Set this to zero to disable the dispatcher thread monitor.  Defaults
+      to 60 samples per minute.
+    </description>
+    <name>yarn.dispatcher.cpu-monitor.samples-per-min</name>
+    <value>60</value>
+  </property>
+
   <property>
     <description>The expiry interval for application master reporting.</description>
     <name>yarn.am.liveness-monitor.expiry-interval-ms</name>

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/ClusterMetrics.java

@@ -62,6 +62,12 @@ public class ClusterMetrics {
   @Metric("Vcore Utilization") MutableGaugeLong utilizedVirtualCores;
   @Metric("Memory Capability") MutableGaugeLong capabilityMB;
   @Metric("Vcore Capability") MutableGaugeLong capabilityVirtualCores;
+  @Metric("RM Event Processor CPU Usage 60 second Avg") MutableGaugeLong
+    rmEventProcCPUAvg;
+  @Metric("RM Event Processor CPU Usage 60 second Max") MutableGaugeLong
+    rmEventProcCPUMax;
+
+  private boolean rmEventProcMonitorEnable = false;
 
   private static final MetricsInfo RECORD_INFO = info("ClusterMetrics",
   "Metrics for the Yarn Cluster");
@@ -118,6 +124,27 @@ public class ClusterMetrics {
     INSTANCE = null;
   }
   
+  // Indicate whether RM Event Thread CPU Monitor is enabled
+  public void setRmEventProcMonitorEnable(boolean value) {
+    rmEventProcMonitorEnable = value;
+  }
+  public boolean getRmEventProcMonitorEnable() {
+    return rmEventProcMonitorEnable;
+  }
+  // RM Event Processor CPU Usage
+  public long getRmEventProcCPUAvg() {
+    return rmEventProcCPUAvg.value();
+  }
+  public void setRmEventProcCPUAvg(long value) {
+    rmEventProcCPUAvg.set(value);
+  }
+  public long getRmEventProcCPUMax() {
+    return rmEventProcCPUMax.value();
+  }
+  public void setRmEventProcCPUMax(long value) {
+    rmEventProcCPUMax.set(value);
+  }
+
   //Active Nodemanagers
   public int getNumActiveNMs() {
     return numActiveNMs.value();
@@ -292,4 +319,4 @@ public class ClusterMetrics {
   public void incrUtilizedVirtualCores(long delta) {
     utilizedVirtualCores.incr(delta);
   }
-}
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/ResourceManager.java

@@ -48,8 +48,9 @@ import org.apache.hadoop.util.JvmPauseMonitor;
 import org.apache.hadoop.util.ReflectionUtils;
 import org.apache.hadoop.util.ShutdownHookManager;
 import org.apache.hadoop.util.StringUtils;
-import org.apache.hadoop.util.VersionInfo;
+import org.apache.hadoop.util.Time;
 import org.apache.hadoop.util.curator.ZKCuratorManager;
+import org.apache.hadoop.util.VersionInfo;
 import org.apache.hadoop.yarn.YarnUncaughtExceptionHandler;
 import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
@@ -136,6 +137,8 @@ import org.eclipse.jetty.webapp.WebAppContext;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.PrintStream;
+import java.lang.management.ManagementFactory;
+import java.lang.management.ThreadMXBean;
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.net.URL;
@@ -449,7 +452,21 @@ public class ResourceManager extends CompositeService
   }
 
   protected EventHandler<SchedulerEvent> createSchedulerEventDispatcher() {
-    return new EventDispatcher(this.scheduler, "SchedulerEventDispatcher");
+    String dispatcherName = "SchedulerEventDispatcher";
+    EventDispatcher dispatcher;
+    int threadMonitorRate = conf.getInt(
+        YarnConfiguration.YARN_DISPATCHER_CPU_MONITOR_SAMPLES_PER_MIN,
+        YarnConfiguration.DEFAULT_YARN_DISPATCHER_CPU_MONITOR_SAMPLES_PER_MIN);
+
+    if (threadMonitorRate > 0) {
+      dispatcher = new SchedulerEventDispatcher(dispatcherName,
+          threadMonitorRate);
+      ClusterMetrics.getMetrics().setRmEventProcMonitorEnable(true);
+    } else {
+      dispatcher = new EventDispatcher(this.scheduler, dispatcherName);
+    }
+
+    return dispatcher;
   }
 
   protected Dispatcher createDispatcher() {
@@ -1004,7 +1021,95 @@ public class ResourceManager extends CompositeService
     }
   }
 
-  /**
+  @Private
+  private class SchedulerEventDispatcher extends
+      EventDispatcher<SchedulerEvent> {
+
+    private final Thread eventProcessorMonitor;
+
+    SchedulerEventDispatcher(String name, int samplesPerMin) {
+      super(scheduler, name);
+      this.eventProcessorMonitor =
+          new Thread(new EventProcessorMonitor(getEventProcessorId(),
+              samplesPerMin));
+      this.eventProcessorMonitor
+          .setName("ResourceManager Event Processor Monitor");
+    }
+    // EventProcessorMonitor keeps track of how much CPU the EventProcessor
+    // thread is using. It takes a configurable number of samples per minute,
+    // and then reports the Avg and Max of previous 60 seconds as cluster
+    // metrics. Units are usecs per second of CPU used.
+    // Avg is not accurate until one minute of samples have been received.
+    private final class EventProcessorMonitor implements Runnable {
+      private final long tid;
+      private final boolean run;
+      private final ThreadMXBean tmxb;
+      private final ClusterMetrics clusterMetrics = ClusterMetrics.getMetrics();
+      private final int samples;
+      EventProcessorMonitor(long id, int samplesPerMin) {
+        assert samplesPerMin > 0;
+        this.tid = id;
+        this.samples = samplesPerMin;
+        this.tmxb = ManagementFactory.getThreadMXBean();
+        if (clusterMetrics != null &&
+            tmxb != null && tmxb.isThreadCpuTimeSupported()) {
+          this.run = true;
+          clusterMetrics.setRmEventProcMonitorEnable(true);
+        } else {
+          this.run = false;
+        }
+      }
+      public void run() {
+        int index = 0;
+        long[] values = new long[samples];
+        int sleepMs = (60 * 1000) / samples;
+
+        while (run && !isStopped() && !Thread.currentThread().isInterrupted()) {
+          try {
+            long cpuBefore = tmxb.getThreadCpuTime(tid);
+            long wallClockBefore = Time.monotonicNow();
+            Thread.sleep(sleepMs);
+            long wallClockDelta = Time.monotonicNow() - wallClockBefore;
+            long cpuDelta = tmxb.getThreadCpuTime(tid) - cpuBefore;
+
+            // Nanoseconds / Milliseconds = usec per second
+            values[index] = cpuDelta / wallClockDelta;
+
+            index = (index + 1) % samples;
+            long max = 0;
+            long sum = 0;
+            for (int i = 0; i < samples; i++) {
+              sum += values[i];
+              max = Math.max(max, values[i]);
+            }
+            clusterMetrics.setRmEventProcCPUAvg(sum / samples);
+            clusterMetrics.setRmEventProcCPUMax(max);
+          } catch (InterruptedException e) {
+            LOG.error("Returning, interrupted : " + e);
+            return;
+          }
+        }
+      }
+    }
+    @Override
+    protected void serviceStart() throws Exception {
+      super.serviceStart();
+      this.eventProcessorMonitor.start();
+    }
+
+    @Override
+    protected void serviceStop() throws Exception {
+      super.serviceStop();
+      this.eventProcessorMonitor.interrupt();
+      try {
+        this.eventProcessorMonitor.join();
+      } catch (InterruptedException e) {
+        throw new YarnRuntimeException(e);
+      }
+    }
+  }
+
+    /**
    * Transition to standby state in a new thread. The transition operation is
    * asynchronous to avoid deadlock caused by cyclic dependency.
    */

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/MetricsOverviewTable.java

@@ -204,7 +204,8 @@ public class MetricsOverviewTable extends HtmlBlock {
     }
 
     SchedulerInfo schedulerInfo = new SchedulerInfo(this.rm);
-    
+    int schedBusy = clusterMetrics.getRmSchedulerBusyPercent();
+
     div.h3("Scheduler Metrics").
     table("#schedulermetricsoverview").
     thead().$class("ui-widget-header").
@@ -215,6 +216,7 @@ public class MetricsOverviewTable extends HtmlBlock {
         th().$class("ui-state-default").__("Maximum Allocation").__().
         th().$class("ui-state-default")
             .__("Maximum Cluster Application Priority").__().
+        th().$class("ui-state-default").__("Scheduler Busy %").__().
         __().
         __().
     tbody().$class("ui-widget-content").
@@ -225,6 +227,7 @@ public class MetricsOverviewTable extends HtmlBlock {
         td(schedulerInfo.getMinAllocation().toString()).
         td(schedulerInfo.getMaxAllocation().toString()).
         td(String.valueOf(schedulerInfo.getMaxClusterLevelAppPriority())).
+        td(schedBusy == -1 ? UNAVAILABLE : String.valueOf(schedBusy)).
         __().
         __().__();
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/dao/ClusterMetricsInfo.java

@@ -57,6 +57,7 @@ public class ClusterMetricsInfo {
   private long totalVirtualCores;
   private int utilizedMBPercent;
   private int utilizedVirtualCoresPercent;
+  private int rmSchedulerBusyPercent;
   private int totalNodes;
   private int lostNodes;
   private int unhealthyNodes;
@@ -143,7 +144,11 @@ public class ClusterMetricsInfo {
     this.utilizedVirtualCoresPercent = baseCores <= 0 ? 0 :
         (int) (clusterMetrics.getUtilizedVirtualCores() * 100 /
             baseCores);
-
+    // Scheduler Busy is in usec per sec, so to get percent divide by 10^4
+    // Set to -1 if disabled.
+    this.rmSchedulerBusyPercent =
+        clusterMetrics.getRmEventProcMonitorEnable() ?
+        (int)(clusterMetrics.getRmEventProcCPUAvg() / 10000L) : -1;
     this.activeNodes = clusterMetrics.getNumActiveNMs();
     this.lostNodes = clusterMetrics.getNumLostNMs();
     this.unhealthyNodes = clusterMetrics.getUnhealthyNMs();
@@ -271,6 +276,10 @@ public class ClusterMetricsInfo {
     return utilizedVirtualCoresPercent;
   }
 
+  public int getRmSchedulerBusyPercent() {
+    return rmSchedulerBusyPercent;
+  }
+
   public void setContainersReserved(int containersReserved) {
     this.containersReserved = containersReserved;
   }
@@ -383,6 +392,10 @@ public class ClusterMetricsInfo {
     this.utilizedVirtualCoresPercent = utilizedVirtualCoresPercent;
   }
 
+  public void setRmSchedulerBusyPercent(int rmSchedulerBusyPercent) {
+    this.rmSchedulerBusyPercent = rmSchedulerBusyPercent;
+  }
+
   public ResourceInfo getTotalClusterResourcesAcrossPartition() {
     return totalClusterResourcesAcrossPartition;
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/TestNodesPage.java

@@ -52,7 +52,7 @@ public class TestNodesPage {
 
   // Number of Actual Table Headers for NodesPage.NodesBlock might change in
   // future. In that case this value should be adjusted to the new value.
-  private final int numberOfThInMetricsTable = 22;
+  private final int numberOfThInMetricsTable = 23;
   private final int numberOfActualTableHeaders = 18;
   private final int numberOfThForOpportunisticContainers = 4;
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/TestRMWebServices.java

@@ -474,7 +474,7 @@ public class TestRMWebServices extends JerseyTestBase {
       Exception {
     assertEquals("incorrect number of elements", 1, json.length());
     JSONObject clusterinfo = json.getJSONObject("clusterMetrics");
-    assertEquals("incorrect number of elements", 31, clusterinfo.length());
+    assertEquals("incorrect number of elements", 32, clusterinfo.length());
     verifyClusterMetrics(
         clusterinfo.getInt("appsSubmitted"), clusterinfo.getInt("appsCompleted"),
         clusterinfo.getInt("reservedMB"), clusterinfo.getInt("availableMB"),