YARN-2990. FairScheduler's delay-scheduling always waits for node-local and rack-local delays, even for off-rack-only requests. (kasha)

hadoop-yarn-project/CHANGES.txt

@@ -257,6 +257,9 @@ Release 2.7.0 - UNRELEASED
 
   OPTIMIZATIONS
 
+    YARN-2990. FairScheduler's delay-scheduling always waits for node-local and 
+    rack-local delays, even for off-rack-only requests. (kasha)
+
   BUG FIXES
 
     YARN-3071. Remove invalid char from sample conf in doc of FairScheduler.

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

@@ -541,6 +541,10 @@ private Resource assignContainer(
     }
   }
 
+  private boolean hasNodeOrRackLocalRequests(Priority priority) {
+    return getResourceRequests(priority).size() > 1;
+  }
+
   private Resource assignContainer(FSSchedulerNode node, boolean reserved) {
     if (LOG.isDebugEnabled()) {
       LOG.debug("Node offered to app: " + getName() + " reserved: " + reserved);
@@ -615,10 +619,13 @@ private Resource assignContainer(FSSchedulerNode node, boolean reserved) {
           continue;
         }
 
-        if (offSwitchRequest != null && offSwitchRequest.getNumContainers() != 0
-            && allowedLocality.equals(NodeType.OFF_SWITCH)) {
-          return assignContainer(node, offSwitchRequest,
-              NodeType.OFF_SWITCH, reserved);
+        if (offSwitchRequest != null &&
+            offSwitchRequest.getNumContainers() != 0) {
+          if (!hasNodeOrRackLocalRequests(priority) ||
+              allowedLocality.equals(NodeType.OFF_SWITCH)) {
+            return assignContainer(
+                node, offSwitchRequest, NodeType.OFF_SWITCH, reserved);
+          }
         }
       }
     }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/TestContinuousScheduling.java

@@ -0,0 +1,114 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.metrics2.lib.MutableRate;
+import org.apache.hadoop.metrics2.util.SampleStat;
+import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
+import org.apache.hadoop.yarn.api.records.ContainerId;
+import org.apache.hadoop.yarn.api.records.Resource;
+import org.apache.hadoop.yarn.api.records.ResourceRequest;
+import org.apache.hadoop.yarn.server.resourcemanager.MockNodes;
+import org.apache.hadoop.yarn.server.resourcemanager.MockRM;
+import org.apache.hadoop.yarn.server.resourcemanager.rmnode.RMNode;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.NodeAddedSchedulerEvent;
+
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event
+    .NodeUpdateSchedulerEvent;
+import org.apache.hadoop.yarn.util.resource.Resources;
+import org.junit.After;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+public class TestContinuousScheduling extends FairSchedulerTestBase {
+  private MockClock mockClock;
+
+  @Override
+  public Configuration createConfiguration() {
+    Configuration conf = super.createConfiguration();
+    conf.setBoolean(
+        FairSchedulerConfiguration.CONTINUOUS_SCHEDULING_ENABLED, true);
+    conf.setInt(FairSchedulerConfiguration.LOCALITY_DELAY_NODE_MS, 100);
+    conf.setInt(FairSchedulerConfiguration.LOCALITY_DELAY_RACK_MS, 100);
+    return conf;
+  }
+
+  @Before
+  public void setup() {
+    mockClock = new MockClock();
+    conf = createConfiguration();
+    resourceManager = new MockRM(conf);
+    resourceManager.start();
+
+    scheduler = (FairScheduler) resourceManager.getResourceScheduler();
+    scheduler.setClock(mockClock);
+
+    assertTrue(scheduler.isContinuousSchedulingEnabled());
+    assertEquals(
+        FairSchedulerConfiguration.DEFAULT_CONTINUOUS_SCHEDULING_SLEEP_MS,
+        scheduler.getContinuousSchedulingSleepMs());
+    assertEquals(mockClock, scheduler.getClock());
+  }
+
+  @After
+  public void teardown() {
+    if (resourceManager != null) {
+      resourceManager.stop();
+      resourceManager = null;
+    }
+  }
+
+  @Test (timeout = 60000)
+  public void testSchedulingDelay() throws InterruptedException {
+    // Add one node
+    String host = "127.0.0.1";
+    RMNode node1 = MockNodes.newNodeInfo(
+        1, Resources.createResource(4096, 4), 1, host);
+    NodeAddedSchedulerEvent nodeEvent1 = new NodeAddedSchedulerEvent(node1);
+    scheduler.handle(nodeEvent1);
+    NodeUpdateSchedulerEvent nodeUpdateEvent = new NodeUpdateSchedulerEvent(node1);
+    scheduler.handle(nodeUpdateEvent);
+
+    // Create one application and submit one each of node-local, rack-local
+    // and ANY requests
+    ApplicationAttemptId appAttemptId =
+        createAppAttemptId(this.APP_ID++, this.ATTEMPT_ID++);
+    scheduler.addApplication(appAttemptId.getApplicationId(), "queue11", "user11", false);
+    scheduler.addApplicationAttempt(appAttemptId, false, false);
+    List<ResourceRequest> ask = new ArrayList<>();
+    ask.add(createResourceRequest(1024, 1, ResourceRequest.ANY, 1, 1, true));
+    scheduler.allocate(
+        appAttemptId, ask, new ArrayList<ContainerId>(), null, null);
+    FSAppAttempt app = scheduler.getSchedulerApp(appAttemptId);
+
+    // Advance time and let continuous scheduling kick in
+    mockClock.tick(1);
+    while (1024 != app.getCurrentConsumption().getMemory()) {
+      Thread.sleep(100);
+    }
+    assertEquals(1024, app.getCurrentConsumption().getMemory());
+  }
+}