YARN-9756: Create metric that sums total memory/vcores preempted per round. Contributed by Manikandan R (manirajv06).

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

@@ -24,6 +24,7 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Map;
 
+import com.google.common.annotations.VisibleForTesting;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceAudience.Private;
 import org.apache.hadoop.conf.Configuration;
@@ -76,6 +77,10 @@ public class QueueMetrics implements MetricsSource {
   @Metric("# of active applications") MutableGaugeInt activeApplications;
   @Metric("App Attempt First Container Allocation Delay")
     MutableRate appAttemptFirstContainerAllocationDelay;
+  @Metric("Aggregate total of preempted memory MB")
+    MutableCounterLong aggregateMemoryMBPreempted;
+  @Metric("Aggregate total of preempted vcores")
+    MutableCounterLong aggregateVcoresPreempted;
 
   //Metrics updated only for "default" partition
   @Metric("Allocated memory in MB") MutableGaugeLong allocatedMB;
@@ -552,6 +557,14 @@ public class QueueMetrics implements MetricsSource {
     }
   }
 
+  public void updatePreemptedResources(Resource res) {
+    aggregateMemoryMBPreempted.incr(res.getMemorySize());
+    aggregateVcoresPreempted.incr(res.getVirtualCores());
+    if (parent != null) {
+      parent.updatePreemptedResources(res);
+    }
+  }
+
   public void reserveResource(String partition, String user, Resource res) {
     if(partition == null || partition.equals(RMNodeLabelsManager.NO_LABEL)) {
       reserveResource(user, res);
@@ -732,4 +745,14 @@ public class QueueMetrics implements MetricsSource {
   public long getAggregatePreemptedContainers() {
     return aggregateContainersPreempted.value();
   }
+
+  @VisibleForTesting
+  public long getAggregateMemoryMBPreempted() {
+    return aggregateMemoryMBPreempted.value();
+  }
+
+  @VisibleForTesting
+  public long getAggregateVcoresPreempted() {
+    return aggregateVcoresPreempted.value();
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacityScheduler.java

@@ -2115,6 +2115,7 @@ public class CapacityScheduler extends
         / DateUtils.MILLIS_PER_SECOND;
     qMetrics.updatePreemptedMemoryMBSeconds(mbSeconds);
     qMetrics.updatePreemptedVcoreSeconds(vcSeconds);
+    qMetrics.updatePreemptedResources(containerResource);
   }
 
   @Lock(Lock.NoLock.class)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/TestCapacitySchedulerSurgicalPreemption.java

@@ -185,6 +185,11 @@ public class TestCapacitySchedulerSurgicalPreemption
     Assert.assertEquals("Number of preempted containers incorrectly recorded:",
         4, cs.getQueue("root").getMetrics().getAggregatePreemptedContainers());
 
+    Assert.assertEquals("Amount of preempted memory incorrectly recorded:",
+	4 * GB, cs.getQueue("root").getMetrics().getAggregateMemoryMBPreempted());
+    Assert.assertEquals("Number of preempted vcores incorrectly recorded:",
+	4, cs.getQueue("root").getMetrics().getAggregateVcoresPreempted());
+
     rm1.close();
   }