HDDS-351. Add chill mode state to SCM.

Contributed by Ajay Kumar.

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/HddsConfigKeys.java

@@ -75,4 +75,10 @@ public final class HddsConfigKeys {
       "hdds.container.close.threshold";
   public static final float HDDS_CONTAINER_CLOSE_THRESHOLD_DEFAULT = 0.9f;
 
+  // % of containers which should have at least one reported replica
+  // before SCM comes out of chill mode.
+  public static final String HDDS_SCM_CHILLMODE_THRESHOLD_PCT =
+      "hdds.scm.chillmode.threshold.pct";
+  public static final double HDDS_SCM_CHILLMODE_THRESHOLD_PCT_DEFAULT = 0.99;
+
 }

hadoop-hdds/common/src/main/resources/ozone-default.xml

@@ -1112,6 +1112,15 @@
     </description>
   </property>
 
+  <property>
+    <name>hdds.scm.chillmode.threshold.pct</name>
+    <value>0.99</value>
+    <tag>HDDS,SCM,OPERATION</tag>
+    <description> % of containers which should have at least one
+      reported replica before SCM comes out of chill mode.
+    </description>
+  </property>
+
   <property>
     <name>hdds.container.action.max.limit</name>
     <value>20</value>

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/container/ContainerMapping.java

@@ -33,6 +33,7 @@ import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerInfo;
 import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineID;
 import org.apache.hadoop.hdds.scm.events.SCMEvents;
 import org.apache.hadoop.hdds.scm.exceptions.SCMException;
+import org.apache.hadoop.hdds.scm.exceptions.SCMException.ResultCodes;
 import org.apache.hadoop.hdds.scm.node.NodeManager;
 import org.apache.hadoop.hdds.scm.pipelines.PipelineSelector;
 import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
@@ -210,6 +211,10 @@ public class ContainerMapping implements Mapping {
         // For close containers create pipeline from datanodes with replicas
         Set<DatanodeDetails> dnWithReplicas = containerStateManager
             .getContainerReplicas(contInfo.containerID());
+        if (dnWithReplicas.size() == 0) {
+          throw new SCMException("Can't create a pipeline for container with "
+              + "no replica.", ResultCodes.NO_REPLICA_FOUND);
+        }
         pipeline =
             new Pipeline(dnWithReplicas.iterator().next().getUuidString(),
                 contInfo.getState(), ReplicationType.STAND_ALONE,

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/events/SCMEvents.java

@@ -45,6 +45,7 @@ import org.apache.hadoop.hdds.scm.container.replication.ReplicationManager
     .ReplicationCompleted;
 import org.apache.hadoop.hdds.scm.container.replication.ReplicationRequest;
 
+import org.apache.hadoop.hdds.scm.server.SCMDatanodeProtocolServer.NodeRegistrationContainerReport;
 import org.apache.hadoop.hdds.server.events.Event;
 import org.apache.hadoop.hdds.server.events.TypedEvent;
 import org.apache.hadoop.ozone.protocol.commands.CommandForDatanode;
@@ -60,6 +61,15 @@ public final class SCMEvents {
    */
   public static final TypedEvent<NodeReportFromDatanode> NODE_REPORT =
       new TypedEvent<>(NodeReportFromDatanode.class, "Node_Report");
+
+  /**
+   * Event generated on DataNode registration.
+   */
+  public static final TypedEvent<NodeRegistrationContainerReport>
+      NODE_REGISTRATION_CONT_REPORT = new TypedEvent<>(
+      NodeRegistrationContainerReport.class,
+      "Node_Registration_Container_Report");
+
   /**
    * ContainerReports are send out by Datanodes. This report is received by
    * SCMDatanodeHeartbeatDispatcher and Container_Report Event

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/server/SCMChillModeManager.java

@@ -0,0 +1,198 @@
+/*
+ * 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.hdds.scm.server;
+
+import com.google.common.annotations.VisibleForTesting;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicLong;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdds.HddsConfigKeys;
+import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerInfo;
+import org.apache.hadoop.hdds.scm.events.SCMEvents;
+import org.apache.hadoop.hdds.scm.server.SCMDatanodeProtocolServer
+    .NodeRegistrationContainerReport;
+import org.apache.hadoop.hdds.server.events.EventHandler;
+import org.apache.hadoop.hdds.server.events.EventPublisher;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * StorageContainerManager enters chill mode on startup to allow system to
+ * reach a stable state before becoming fully functional. SCM will wait
+ * for certain resources to be reported before coming out of chill mode.
+ *
+ * ChillModeExitRule defines format to define new rules which must be satisfied
+ * to exit Chill mode.
+ * ContainerChillModeRule defines the only exit criteria right now.
+ * On every new datanode registration event this class adds replicas
+ * for reported containers and validates if cutoff threshold for
+ * containers is meet.
+ */
+public class SCMChillModeManager implements
+    EventHandler<NodeRegistrationContainerReport> {
+
+  private static final Logger LOG =
+      LoggerFactory.getLogger(SCMChillModeManager.class);
+  private AtomicBoolean inChillMode = new AtomicBoolean(true);
+  private AtomicLong containerWithMinReplicas = new AtomicLong(0);
+  private Map<String, ChillModeExitRule> exitRules = new HashMap(1);
+  private Configuration config;
+  private static final String CONT_EXIT_RULE = "ContainerChillModeRule";
+
+  SCMChillModeManager(Configuration conf, List<ContainerInfo> allContainers) {
+    this.config = conf;
+    exitRules
+        .put(CONT_EXIT_RULE, new ContainerChillModeRule(config, allContainers));
+  }
+
+  private void validateChillModeExitRules(EventPublisher eventQueue) {
+    for (ChillModeExitRule exitRule : exitRules.values()) {
+      if (!exitRule.validate()) {
+        return;
+      }
+    }
+    exitChillMode(eventQueue);
+  }
+
+  private void exitChillMode(EventPublisher eventQueue) {
+    LOG.info("SCM exiting chill mode.");
+    setInChillMode(false);
+    // Emit event to ReplicationManager to start replication.
+    eventQueue.fireEvent(SCMEvents.START_REPLICATION, true);
+
+    // TODO: Remove handler registration as there is no need to listen to
+    // register events anymore.
+
+    for (ChillModeExitRule e : exitRules.values()) {
+      e.cleanup();
+    }
+  }
+
+  @Override
+  public void onMessage(
+      NodeRegistrationContainerReport nodeRegistrationContainerReport,
+      EventPublisher publisher) {
+    if (getInChillMode()) {
+      exitRules.get(CONT_EXIT_RULE).process(nodeRegistrationContainerReport);
+      validateChillModeExitRules(publisher);
+    }
+  }
+
+  public boolean getInChillMode() {
+    return inChillMode.get();
+  }
+
+  public void setInChillMode(boolean inChillMode) {
+    this.inChillMode.set(inChillMode);
+  }
+
+  /**
+   * Interface for defining chill mode exit rules.
+   *
+   * @param <T>
+   */
+  public interface ChillModeExitRule<T> {
+
+    boolean validate();
+
+    void process(T report);
+
+    void cleanup();
+  }
+
+  /**
+   * Class defining Chill mode exit criteria for Containers.
+   */
+  public class ContainerChillModeRule implements
+      ChillModeExitRule<NodeRegistrationContainerReport> {
+
+    // Required cutoff % for containers with at least 1 reported replica.
+    private double chillModeCutoff;
+    // Containers read from scm db.
+    private Map<Long, ContainerInfo> containerMap;
+    private double maxContainer;
+
+    public ContainerChillModeRule(Configuration conf,
+        List<ContainerInfo> containers) {
+      chillModeCutoff = conf
+          .getDouble(HddsConfigKeys.HDDS_SCM_CHILLMODE_THRESHOLD_PCT,
+              HddsConfigKeys.HDDS_SCM_CHILLMODE_THRESHOLD_PCT_DEFAULT);
+      containerMap = new ConcurrentHashMap<>();
+      if(containers != null) {
+        containers.forEach(c -> {
+          if (c != null) {
+            containerMap.put(c.getContainerID(), c);
+          }
+        });
+        maxContainer = containers.size();
+      }
+    }
+
+    @Override
+    public boolean validate() {
+      if (maxContainer == 0) {
+        return true;
+      }
+      return getCurrentContainerThreshold() >= chillModeCutoff;
+    }
+
+    @VisibleForTesting
+    public double getCurrentContainerThreshold() {
+      return (containerWithMinReplicas.doubleValue() / maxContainer);
+    }
+
+    @Override
+    public void process(NodeRegistrationContainerReport reportsProto) {
+      if (maxContainer == 0) {
+        // No container to check.
+        return;
+      }
+
+      reportsProto.getReport().getReportsList().forEach(c -> {
+        if (containerMap.containsKey(c.getContainerID())) {
+          if(containerMap.remove(c.getContainerID()) != null) {
+            containerWithMinReplicas.getAndAdd(1);
+          }
+        }
+      });
+
+      LOG.info("SCM in chill mode. {} % containers have at least one reported "
+          + "replica.", (containerWithMinReplicas.get() / maxContainer) * 100);
+    }
+
+    @Override
+    public void cleanup() {
+      containerMap.clear();
+    }
+  }
+
+  @VisibleForTesting
+  public static Logger getLogger() {
+    return LOG;
+  }
+
+  @VisibleForTesting
+  public double getCurrentContainerThreshold() {
+    return ((ContainerChillModeRule) exitRules.get(CONT_EXIT_RULE))
+        .getCurrentContainerThreshold();
+  }
+}

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/server/SCMDatanodeProtocolServer.java

@@ -73,6 +73,8 @@ import static org.apache.hadoop.hdds.protocol.proto
 
 
 import org.apache.hadoop.hdds.scm.HddsServerUtil;
+import org.apache.hadoop.hdds.scm.events.SCMEvents;
+import org.apache.hadoop.hdds.scm.server.SCMDatanodeHeartbeatDispatcher.ReportFromDatanode;
 import org.apache.hadoop.hdds.server.events.EventPublisher;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.ipc.ProtobufRpcEngine;
@@ -120,6 +122,7 @@ public class SCMDatanodeProtocolServer implements
   private final StorageContainerManager scm;
   private final InetSocketAddress datanodeRpcAddress;
   private final SCMDatanodeHeartbeatDispatcher heartbeatDispatcher;
+  private final EventPublisher eventPublisher;
 
   public SCMDatanodeProtocolServer(final OzoneConfiguration conf,
       StorageContainerManager scm, EventPublisher eventPublisher)
@@ -129,6 +132,7 @@ public class SCMDatanodeProtocolServer implements
     Preconditions.checkNotNull(eventPublisher, "EventPublisher cannot be null");
 
     this.scm = scm;
+    this.eventPublisher = eventPublisher;
     final int handlerCount =
         conf.getInt(OZONE_SCM_HANDLER_COUNT_KEY,
             OZONE_SCM_HANDLER_COUNT_DEFAULT);
@@ -197,6 +201,9 @@ public class SCMDatanodeProtocolServer implements
         == SCMRegisteredResponseProto.ErrorCode.success) {
       scm.getScmContainerManager().processContainerReports(datanodeDetails,
           containerReportsProto, true);
+      eventPublisher.fireEvent(SCMEvents.NODE_REGISTRATION_CONT_REPORT,
+          new NodeRegistrationContainerReport(datanodeDetails,
+              containerReportsProto));
     }
     return getRegisteredResponse(registeredCommand);
   }
@@ -305,4 +312,16 @@ public class SCMDatanodeProtocolServer implements
     IOUtils.cleanupWithLogger(LOG, scm.getScmNodeManager());
   }
 
+  /**
+   * Wrapper class for events with the datanode origin.
+   */
+  public static class NodeRegistrationContainerReport extends
+      ReportFromDatanode<ContainerReportsProto> {
+
+    public NodeRegistrationContainerReport(DatanodeDetails datanodeDetails,
+        ContainerReportsProto report) {
+      super(datanodeDetails, report);
+    }
+  }
+
 }

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/server/StorageContainerManager.java

@@ -176,6 +176,7 @@ public final class StorageContainerManager extends ServiceRuntimeInfoImpl
   private final LeaseManager<Long> commandWatcherLeaseManager;
 
   private final ReplicationActivityStatus replicationStatus;
+  private final SCMChillModeManager scmChillModeManager;
 
   /**
    * Creates a new StorageContainerManager. Configuration will be updated
@@ -231,7 +232,8 @@ public final class StorageContainerManager extends ServiceRuntimeInfoImpl
     ContainerReportHandler containerReportHandler =
         new ContainerReportHandler(scmContainerManager, node2ContainerMap,
             replicationStatus);
-
+    scmChillModeManager = new SCMChillModeManager(conf,
+        getScmContainerManager().getStateManager().getAllContainers());
     PipelineActionEventHandler pipelineActionEventHandler =
         new PipelineActionEventHandler();
 
@@ -253,6 +255,8 @@ public final class StorageContainerManager extends ServiceRuntimeInfoImpl
     eventQueue.addHandler(SCMEvents.PIPELINE_ACTIONS,
         pipelineActionEventHandler);
     eventQueue.addHandler(SCMEvents.PIPELINE_CLOSE, pipelineCloseHandler);
+    eventQueue.addHandler(SCMEvents.NODE_REGISTRATION_CONT_REPORT,
+        scmChillModeManager);
 
     long watcherTimeout =
         conf.getTimeDuration(ScmConfigKeys.HDDS_SCM_WATCHER_TIMEOUT,
@@ -619,9 +623,9 @@ public final class StorageContainerManager extends ServiceRuntimeInfoImpl
         "server", getDatanodeProtocolServer().getDatanodeRpcAddress()));
     getDatanodeProtocolServer().start();
 
-    replicationStatus.start();
     httpServer.start();
     scmBlockManager.start();
+    replicationStatus.start();
     replicationManager.start();
     setStartTime();
   }
@@ -809,6 +813,15 @@ public final class StorageContainerManager extends ServiceRuntimeInfoImpl
     return id2StatMap;
   }
 
+  public boolean isInChillMode() {
+    return scmChillModeManager.getInChillMode();
+  }
+
+  @VisibleForTesting
+  public double getCurrentContainerThreshold() {
+    return scmChillModeManager.getCurrentContainerThreshold();
+  }
+
   /**
    * Startup options.
    */

hadoop-hdds/server-scm/src/test/java/org/apache/hadoop/hdds/scm/HddsTestUtils.java

@@ -0,0 +1,85 @@
+/*
+ * 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.hdds.scm;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.commons.lang3.RandomUtils;
+import org.apache.hadoop.hdds.protocol.proto
+    .StorageContainerDatanodeProtocolProtos;
+import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerInfo;
+import org.apache.hadoop.hdds.scm.server.SCMDatanodeProtocolServer
+    .NodeRegistrationContainerReport;
+
+/**
+ * Stateless helper functions for Hdds tests.
+ */
+public final class HddsTestUtils {
+
+  private HddsTestUtils() {
+  }
+
+  /**
+   * Create Command Status report object.
+   *
+   * @param numOfContainers number of containers to be included in report.
+   * @return CommandStatusReportsProto
+   */
+  public static NodeRegistrationContainerReport
+      createNodeRegistrationContainerReport(int numOfContainers) {
+    return new NodeRegistrationContainerReport(
+        TestUtils.randomDatanodeDetails(),
+        TestUtils.getRandomContainerReports(numOfContainers));
+  }
+
+  /**
+   * Create NodeRegistrationContainerReport object.
+   *
+   * @param dnContainers List of containers to be included in report
+   * @return NodeRegistrationContainerReport
+   */
+  public static NodeRegistrationContainerReport
+      createNodeRegistrationContainerReport(List<ContainerInfo> dnContainers) {
+    List<StorageContainerDatanodeProtocolProtos.ContainerInfo>
+        containers = new ArrayList<>();
+    dnContainers.forEach(c -> {
+      containers.add(TestUtils.getRandomContainerInfo(c.getContainerID()));
+    });
+    return new NodeRegistrationContainerReport(
+        TestUtils.randomDatanodeDetails(),
+        TestUtils.getContainerReports(containers));
+  }
+
+  /**
+   * Creates list of ContainerInfo.
+   *
+   * @param numContainers number of ContainerInfo to be included in list.
+   * @return List<ContainerInfo>
+   */
+  public static List<ContainerInfo> getContainerInfo(int numContainers) {
+    List<ContainerInfo> containerInfoList = new ArrayList<>();
+    for (int i = 0; i < numContainers; i++) {
+      ContainerInfo.Builder builder = new ContainerInfo.Builder();
+      containerInfoList.add(builder
+          .setContainerID(RandomUtils.nextLong())
+          .build());
+    }
+    return containerInfoList;
+  }
+
+}

hadoop-hdds/server-scm/src/test/java/org/apache/hadoop/hdds/scm/server/TestSCMChillModeManager.java

@@ -0,0 +1,115 @@
+/*
+ * 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.hdds.scm.server;
+
+import static org.junit.Assert.assertTrue;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdds.conf.OzoneConfiguration;
+import org.apache.hadoop.hdds.scm.HddsTestUtils;
+import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerInfo;
+import org.apache.hadoop.hdds.scm.events.SCMEvents;
+import org.apache.hadoop.hdds.server.events.EventQueue;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.BeforeClass;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.Timeout;
+
+/** Test class for SCMChillModeManager.
+ */
+public class TestSCMChillModeManager {
+
+  private static EventQueue queue;
+  private SCMChillModeManager scmChillModeManager;
+  private static Configuration config;
+  private List<ContainerInfo> containers;
+
+  @Rule
+  public Timeout timeout = new Timeout(1000 * 20);
+
+  @BeforeClass
+  public static void setUp() {
+    queue = new EventQueue();
+    config = new OzoneConfiguration();
+  }
+
+  @Test
+  public void testChillModeState() throws Exception {
+    // Test 1: test for 0 containers
+    testChillMode(0);
+
+    // Test 2: test for 20 containers
+    testChillMode(20);
+  }
+
+  @Test
+  public void testChillModeStateWithNullContainers() {
+    new SCMChillModeManager(config, null);
+  }
+
+  private void testChillMode(int numContainers) throws Exception {
+    containers = new ArrayList<>();
+    containers.addAll(HddsTestUtils.getContainerInfo(numContainers));
+    scmChillModeManager = new SCMChillModeManager(config, containers);
+    queue.addHandler(SCMEvents.NODE_REGISTRATION_CONT_REPORT,
+        scmChillModeManager);
+    assertTrue(scmChillModeManager.getInChillMode());
+    queue.fireEvent(SCMEvents.NODE_REGISTRATION_CONT_REPORT,
+        HddsTestUtils.createNodeRegistrationContainerReport(containers));
+    GenericTestUtils.waitFor(() -> {
+      return !scmChillModeManager.getInChillMode();
+    }, 100, 1000 * 5);
+  }
+
+  @Test
+  public void testChillModeExitRule() throws Exception {
+    containers = new ArrayList<>();
+    containers.addAll(HddsTestUtils.getContainerInfo(25 * 4));
+    scmChillModeManager = new SCMChillModeManager(config, containers);
+    queue.addHandler(SCMEvents.NODE_REGISTRATION_CONT_REPORT,
+        scmChillModeManager);
+    assertTrue(scmChillModeManager.getInChillMode());
+
+    testContainerThreshold(containers.subList(0, 25), 0.25);
+    assertTrue(scmChillModeManager.getInChillMode());
+    testContainerThreshold(containers.subList(25, 50), 0.50);
+    assertTrue(scmChillModeManager.getInChillMode());
+    testContainerThreshold(containers.subList(50, 75), 0.75);
+    assertTrue(scmChillModeManager.getInChillMode());
+    testContainerThreshold(containers.subList(75, 100), 1.0);
+
+    GenericTestUtils.waitFor(() -> {
+      return !scmChillModeManager.getInChillMode();
+    }, 100, 1000 * 5);
+  }
+
+  private void testContainerThreshold(List<ContainerInfo> dnContainers,
+      double expectedThreshold)
+      throws Exception {
+    queue.fireEvent(SCMEvents.NODE_REGISTRATION_CONT_REPORT,
+        HddsTestUtils.createNodeRegistrationContainerReport(dnContainers));
+    GenericTestUtils.waitFor(() -> {
+      double threshold = scmChillModeManager.getCurrentContainerThreshold();
+      return threshold == expectedThreshold;
+    }, 100, 2000 * 9);
+  }
+
+}

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/MiniOzoneCluster.java

@@ -178,10 +178,25 @@ public interface MiniOzoneCluster {
   void shutdownHddsDatanode(DatanodeDetails dn) throws IOException;
 
   /**
-   * Shutdown the MiniOzoneCluster.
+   * Shutdown the MiniOzoneCluster and delete the storage dirs.
    */
   void shutdown();
 
+  /**
+   * Stop the MiniOzoneCluster without any cleanup.
+   */
+  void stop();
+
+  /**
+   * Start Scm.
+   */
+  void startScm() throws IOException;
+
+  /**
+   * Start DataNodes.
+   */
+  void startHddsDatanodes();
+
   /**
    * Builder class for MiniOzoneCluster.
    */
@@ -209,6 +224,7 @@ public interface MiniOzoneCluster {
     protected int numOfOmHandlers = 20;
     protected int numOfScmHandlers = 20;
     protected int numOfDatanodes = 1;
+    protected boolean  startDataNodes = true;
 
     protected Builder(OzoneConfiguration conf) {
       this.conf = conf;
@@ -229,6 +245,11 @@ public interface MiniOzoneCluster {
       return this;
     }
 
+    public Builder setStartDataNodes(boolean startDataNodes) {
+      this.startDataNodes = startDataNodes;
+      return this;
+    }
+
     /**
      * Sets the SCM id.
      *

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/MiniOzoneClusterImpl.java

@@ -34,6 +34,7 @@ import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.ozone.client.OzoneClient;
 import org.apache.hadoop.ozone.client.OzoneClientFactory;
 import org.apache.hadoop.ozone.client.rest.OzoneException;
+import org.apache.hadoop.ozone.common.Storage.StorageState;
 import org.apache.hadoop.ozone.om.OMConfigKeys;
 import org.apache.hadoop.ozone.om.OzoneManager;
 import org.apache.hadoop.hdds.scm.server.SCMStorage;
@@ -276,32 +277,54 @@ public final class MiniOzoneClusterImpl implements MiniOzoneCluster {
       File baseDir = new File(GenericTestUtils.getTempPath(
           MiniOzoneClusterImpl.class.getSimpleName() + "-" +
               scm.getClientProtocolServer().getScmInfo().getClusterId()));
+      stop();
       FileUtils.deleteDirectory(baseDir);
+    } catch (IOException e) {
+      LOG.error("Exception while shutting down the cluster.", e);
+    }
+  }
 
+  @Override
+  public void stop() {
+    LOG.info("Stopping the Mini Ozone Cluster");
     if (ozoneManager != null) {
-        LOG.info("Shutting down the OzoneManager");
+      LOG.info("Stopping the OzoneManager");
       ozoneManager.stop();
       ozoneManager.join();
     }
 
     if (scm != null) {
-        LOG.info("Shutting down the StorageContainerManager");
+      LOG.info("Stopping the StorageContainerManager");
       scm.stop();
       scm.join();
     }
 
     if (!hddsDatanodes.isEmpty()) {
-        LOG.info("Shutting down the HddsDatanodes");
+      LOG.info("Shutting the HddsDatanodes");
       for (HddsDatanodeService hddsDatanode : hddsDatanodes) {
         hddsDatanode.stop();
         hddsDatanode.join();
       }
     }
-    } catch (IOException e) {
-      LOG.error("Exception while shutting down the cluster.", e);
   }
+
+  /**
+   * Start Scm.
+   */
+  @Override
+  public void startScm() throws IOException {
+    scm.start();
   }
 
+  /**
+   * Start DataNodes.
+   */
+  @Override
+  public void startHddsDatanodes() {
+    hddsDatanodes.forEach((datanode) -> datanode.start(null));
+  }
+
+
   /**
    * Builder for configuring the MiniOzoneCluster to run.
    */
@@ -324,9 +347,13 @@ public final class MiniOzoneClusterImpl implements MiniOzoneCluster {
       scm.start();
       OzoneManager om = createOM();
       om.start();
-      List<HddsDatanodeService> hddsDatanodes = createHddsDatanodes(scm);
-      hddsDatanodes.forEach((datanode) -> datanode.start(null));
-      return new MiniOzoneClusterImpl(conf, om, scm, hddsDatanodes);
+      final List<HddsDatanodeService> hddsDatanodes = createHddsDatanodes(scm);
+      MiniOzoneClusterImpl cluster = new MiniOzoneClusterImpl(conf, om, scm,
+          hddsDatanodes);
+      if (startDataNodes) {
+        cluster.startHddsDatanodes();
+      }
+      return cluster;
     }
 
     /**
@@ -352,13 +379,30 @@ public final class MiniOzoneClusterImpl implements MiniOzoneCluster {
     private StorageContainerManager createSCM() throws IOException {
       configureSCM();
       SCMStorage scmStore = new SCMStorage(conf);
+      initializeScmStorage(scmStore);
+      return StorageContainerManager.createSCM(null, conf);
+    }
+
+    private void initializeScmStorage(SCMStorage scmStore) throws IOException {
+      if (scmStore.getState() == StorageState.INITIALIZED) {
+        return;
+      }
       scmStore.setClusterId(clusterId);
       if (!scmId.isPresent()) {
         scmId = Optional.of(UUID.randomUUID().toString());
       }
       scmStore.setScmId(scmId.get());
       scmStore.initialize();
-      return StorageContainerManager.createSCM(null, conf);
+    }
+
+    private void initializeOmStorage(OMStorage omStorage) throws IOException{
+      if (omStorage.getState() == StorageState.INITIALIZED) {
+        return;
+      }
+      omStorage.setClusterId(clusterId);
+      omStorage.setScmId(scmId.get());
+      omStorage.setOmId(omId.orElse(UUID.randomUUID().toString()));
+      omStorage.initialize();
     }
 
     /**
@@ -371,10 +415,7 @@ public final class MiniOzoneClusterImpl implements MiniOzoneCluster {
     private OzoneManager createOM() throws IOException {
       configureOM();
       OMStorage omStore = new OMStorage(conf);
-      omStore.setClusterId(clusterId);
-      omStore.setScmId(scmId.get());
-      omStore.setOmId(omId.orElse(UUID.randomUUID().toString()));
-      omStore.initialize();
+      initializeOmStorage(omStore);
       return OzoneManager.createOm(null, conf);
     }
 

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/TestStorageContainerManager.java

@@ -17,59 +17,63 @@
  */
 package org.apache.hadoop.ozone;
 
-import java.io.IOException;
-
-import org.apache.commons.lang3.RandomUtils;
-import org.apache.hadoop.hdds.conf.OzoneConfiguration;
-import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerWithPipeline;
-import org.apache.hadoop.hdds.scm.server.SCMClientProtocolServer;
-import org.apache.hadoop.hdds.scm.server.SCMStorage;
-import org.apache.hadoop.hdds.scm.node.NodeManager;
-import org.apache.hadoop.ozone.container.ContainerTestHelper;
-import org.apache.hadoop.ozone.om.helpers.OmKeyInfo;
-import org.apache.hadoop.ozone.protocol.commands.DeleteBlocksCommand;
-import org.apache.hadoop.ozone.protocol.commands.SCMCommand;
-import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
-import org.apache.hadoop.hdds.protocol.proto.HddsProtos.NodeType;
-import org.apache.hadoop.hdds.protocol.proto.HddsProtos.NodeState;
-import org.apache.hadoop.hdds.protocol.proto
-    .StorageContainerDatanodeProtocolProtos.DeletedBlocksTransaction;
-import org.apache.hadoop.hdds.protocol.proto
-    .StorageContainerDatanodeProtocolProtos.SCMCommandProto;
-import org.apache.hadoop.hdds.scm.server.StorageContainerManager;
-import org.apache.hadoop.hdds.scm.server.StorageContainerManager.StartupOption;
-import org.apache.hadoop.hdds.scm.block.DeletedBlockLog;
-import org.apache.hadoop.hdds.scm.block.SCMBlockDeletingService;
-import org.apache.hadoop.hdds.scm.exceptions.SCMException;
-import org.apache.hadoop.hdds.scm.XceiverClientManager;
-import org.apache.hadoop.hdds.scm.ScmInfo;
-import org.junit.Rule;
-import org.junit.Assert;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.util.List;
-import java.util.HashSet;
-import java.util.Set;
-import java.util.Map;
-import java.util.Collections;
-import java.util.UUID;
-import java.util.concurrent.TimeUnit;
+import static org.apache.hadoop.hdds.HddsConfigKeys.HDDS_CONTAINER_REPORT_INTERVAL;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
-import org.apache.hadoop.ozone.om.helpers.OmKeyLocationInfo;
+import com.google.common.util.concurrent.AtomicDouble;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
+import org.apache.commons.lang3.RandomUtils;
+import org.apache.hadoop.hdds.HddsConfigKeys;
+import org.apache.hadoop.hdds.conf.OzoneConfiguration;
+import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
+import org.apache.hadoop.hdds.protocol.proto.HddsProtos.LifeCycleEvent;
+import org.apache.hadoop.hdds.protocol.proto.HddsProtos.NodeState;
+import org.apache.hadoop.hdds.protocol.proto.HddsProtos.NodeType;
+import org.apache.hadoop.hdds.protocol.proto.StorageContainerDatanodeProtocolProtos.DeletedBlocksTransaction;
+import org.apache.hadoop.hdds.protocol.proto.StorageContainerDatanodeProtocolProtos.SCMCommandProto;
 import org.apache.hadoop.hdds.scm.ScmConfigKeys;
-
+import org.apache.hadoop.hdds.scm.ScmInfo;
+import org.apache.hadoop.hdds.scm.XceiverClientManager;
+import org.apache.hadoop.hdds.scm.block.DeletedBlockLog;
+import org.apache.hadoop.hdds.scm.block.SCMBlockDeletingService;
+import org.apache.hadoop.hdds.scm.container.ContainerMapping;
+import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerInfo;
+import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerWithPipeline;
+import org.apache.hadoop.hdds.scm.exceptions.SCMException;
+import org.apache.hadoop.hdds.scm.node.NodeManager;
+import org.apache.hadoop.hdds.scm.server.SCMChillModeManager;
+import org.apache.hadoop.hdds.scm.server.SCMClientProtocolServer;
+import org.apache.hadoop.hdds.scm.server.SCMStorage;
+import org.apache.hadoop.hdds.scm.server.StorageContainerManager;
+import org.apache.hadoop.hdds.scm.server.StorageContainerManager.StartupOption;
+import org.apache.hadoop.ozone.container.ContainerTestHelper;
+import org.apache.hadoop.ozone.om.helpers.OmKeyInfo;
+import org.apache.hadoop.ozone.om.helpers.OmKeyLocationInfo;
+import org.apache.hadoop.ozone.protocol.commands.DeleteBlocksCommand;
+import org.apache.hadoop.ozone.protocol.commands.SCMCommand;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.Assert;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
 import org.junit.rules.Timeout;
 import org.mockito.Mockito;
-import org.apache.hadoop.test.GenericTestUtils;
-
-import static org.apache.hadoop.hdds
-    .HddsConfigKeys.HDDS_CONTAINER_REPORT_INTERVAL;
-import static org.junit.Assert.fail;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Test class that exercises the StorageContainerManager.
@@ -78,6 +82,8 @@ public class TestStorageContainerManager {
   private static XceiverClientManager xceiverClientManager =
       new XceiverClientManager(
       new OzoneConfiguration());
+  private static final Logger LOG = LoggerFactory
+      .getLogger(TestStorageContainerManager.class);
   /**
    * Set the timeout for every test.
    */
@@ -457,4 +463,92 @@ public class TestStorageContainerManager {
     Assert.assertEquals(clusterId, scmInfo.getClusterId());
     Assert.assertEquals(scmId, scmInfo.getScmId());
   }
+
+  @Test
+  public void testSCMChillMode() throws Exception {
+    OzoneConfiguration conf = new OzoneConfiguration();
+    MiniOzoneCluster.Builder builder = MiniOzoneCluster.newBuilder(conf)
+        .setHbInterval(1000)
+        .setNumDatanodes(3)
+        .setStartDataNodes(false)
+        .setHbProcessorInterval(500);
+    MiniOzoneClusterImpl cluster = (MiniOzoneClusterImpl) builder.build();
+    // Test1: Test chill mode  when there are no containers in system.
+    assertTrue(cluster.getStorageContainerManager().isInChillMode());
+    cluster.startHddsDatanodes();
+    cluster.waitForClusterToBeReady();
+    assertFalse(cluster.getStorageContainerManager().isInChillMode());
+
+    // Test2: Test chill mode  when containers are there in system.
+    // Create {numKeys} random names keys.
+    TestStorageContainerManagerHelper helper =
+        new TestStorageContainerManagerHelper(cluster, conf);
+    Map<String, OmKeyInfo> keyLocations = helper.createKeys(100*2, 4096);
+    final List<ContainerInfo> containers = cluster.getStorageContainerManager()
+        .getScmContainerManager().getStateManager().getAllContainers();
+    GenericTestUtils.waitFor(() -> {
+      return containers.size() > 10;
+    }, 100, 1000);
+
+    // Removing some container to keep them open.
+    containers.remove(0);
+    containers.remove(1);
+    containers.remove(2);
+    containers.remove(3);
+
+    // Close remaining containers
+    ContainerMapping mapping = (ContainerMapping) cluster
+        .getStorageContainerManager().getScmContainerManager();
+    containers.forEach(c -> {
+      try {
+        mapping.updateContainerState(c.getContainerID(),
+            HddsProtos.LifeCycleEvent.FINALIZE);
+        mapping.updateContainerState(c.getContainerID(),
+            LifeCycleEvent.CLOSE);
+      } catch (IOException e) {
+        LOG.info("Failed to change state of open containers.", e);
+      }
+    });
+    cluster.stop();
+
+    GenericTestUtils.LogCapturer logCapturer = GenericTestUtils.LogCapturer
+        .captureLogs(SCMChillModeManager.getLogger());
+    logCapturer.clearOutput();
+    AtomicReference<MiniOzoneCluster> miniCluster = new AtomicReference<>();
+    new Thread(() -> {
+      try {
+        miniCluster.set(builder.setStartDataNodes(false).build());
+      } catch (IOException e) {
+        fail("failed");
+      }
+    }).start();
+
+    StorageContainerManager scm;
+    GenericTestUtils.waitFor(() -> {
+      return miniCluster.get() != null;
+    }, 100, 1000 * 3);
+
+    scm = miniCluster.get().getStorageContainerManager();
+    assertTrue(scm.isInChillMode());
+    assertFalse(logCapturer.getOutput().contains("SCM exiting chill mode."));
+    assertTrue(scm.getCurrentContainerThreshold() == 0);
+    AtomicDouble curThreshold = new AtomicDouble();
+    AtomicDouble lastReportedThreshold = new AtomicDouble();
+    for(HddsDatanodeService dn:miniCluster.get().getHddsDatanodes()){
+      dn.start(null);
+      GenericTestUtils.waitFor(() -> {
+        curThreshold.set(scm.getCurrentContainerThreshold());
+        return curThreshold.get() > lastReportedThreshold.get();
+      }, 100, 1000 * 5);
+      lastReportedThreshold.set(curThreshold.get());
+    }
+    double chillModeCutoff = conf
+        .getDouble(HddsConfigKeys.HDDS_SCM_CHILLMODE_THRESHOLD_PCT,
+            HddsConfigKeys.HDDS_SCM_CHILLMODE_THRESHOLD_PCT_DEFAULT);
+    assertTrue(scm.getCurrentContainerThreshold() >= chillModeCutoff);
+    assertTrue(logCapturer.getOutput().contains("SCM exiting chill mode."));
+    assertFalse(scm.isInChillMode());
+    cluster.shutdown();
+  }
+
 }