Java Code Examples for org.apache.helix.HelixAdmin#rebalance()

/**
 * Update the resources in the destination cluster with the new IdealState settings.
 * @param destZkString the destination Zookeeper server string.
 * @param destClusterName the destination cluster name.
 * @param dryRun run without actual change.
 */
static void updateResourceIdealState(String destZkString, String destClusterName, boolean dryRun) {
  HelixAdmin destAdmin = new ZKHelixAdmin(destZkString);
  Set<String> destResources = new HashSet<>(destAdmin.getResourcesInCluster(destClusterName));

  for (String resource : destResources) {
    IdealState currentIdealState = destAdmin.getResourceIdealState(destClusterName, resource);
    IdealState newIdealState = buildIdealState(resource, currentIdealState.getPartitionSet());
    if (dryRun) {
      System.out.println("Will update " + resource + " to new ideal state " + newIdealState.toString());
    } else {
      destAdmin.setResourceIdealState(destClusterName, resource, newIdealState);
      System.out.println("Updated the ideal state for resource " + resource);
      destAdmin.rebalance(destClusterName, resource, REPLICA_NUMBER, "", "");
      System.out.println("Rebalanced resource " + resource + " with REPLICA_NUM: " + REPLICA_NUMBER);
    }
  }
}
 

/**
 * Populate info on ZooKeeper server and start {@link HelixControllerManager}.
 * @param zkConnectString zk connect string to zk server.
 * @param vcrClusterName the vcr cluster name.
 * @param clusterMap the {@link ClusterMap} to use.
 * @return the created {@link HelixControllerManager}.
 */
public static HelixControllerManager populateZkInfoAndStartController(String zkConnectString, String vcrClusterName,
    ClusterMap clusterMap) {
  HelixZkClient zkClient = DedicatedZkClientFactory.getInstance()
      .buildZkClient(new HelixZkClient.ZkConnectionConfig(zkConnectString), new HelixZkClient.ZkClientConfig());
  try {
    zkClient.setZkSerializer(new ZNRecordSerializer());
    ClusterSetup clusterSetup = new ClusterSetup(zkClient);
    clusterSetup.addCluster(vcrClusterName, true);
    HelixAdmin admin = new ZKHelixAdmin(zkClient);
    // set ALLOW_PARTICIPANT_AUTO_JOIN
    HelixConfigScope configScope = new HelixConfigScopeBuilder(HelixConfigScope.ConfigScopeProperty.CLUSTER).
        forCluster(vcrClusterName).build();
    Map<String, String> helixClusterProperties = new HashMap<>();
    helixClusterProperties.put(ZKHelixManager.ALLOW_PARTICIPANT_AUTO_JOIN, String.valueOf(true));
    admin.setConfig(configScope, helixClusterProperties);
    // set PersistBestPossibleAssignment
    ConfigAccessor configAccessor = new ConfigAccessor(zkClient);
    ClusterConfig clusterConfig = configAccessor.getClusterConfig(vcrClusterName);
    clusterConfig.setPersistBestPossibleAssignment(true);
    configAccessor.setClusterConfig(vcrClusterName, clusterConfig);

    FullAutoModeISBuilder builder = new FullAutoModeISBuilder(helixResource);
    builder.setStateModel(LeaderStandbySMD.name);
    for (PartitionId partitionId : clusterMap.getAllPartitionIds(null)) {
      builder.add(partitionId.toPathString());
    }
    builder.setRebalanceStrategy(CrushEdRebalanceStrategy.class.getName());
    IdealState idealState = builder.build();
    admin.addResource(vcrClusterName, helixResource, idealState);
    admin.rebalance(vcrClusterName, helixResource, 3, "", "");
    HelixControllerManager helixControllerManager = new HelixControllerManager(zkConnectString, vcrClusterName);
    helixControllerManager.syncStart();
    return helixControllerManager;
  } finally {
    zkClient.close();
  }
}
 

/**
 * LockManagerDemo clusterName, numInstances, lockGroupName, numLocks
 * @param args
 * @throws Exception
 */
public static void main(String[] args) throws Exception {
  final String zkAddress = "localhost:2199";
  final String clusterName = "lock-manager-demo";
  final String lockGroupName = "lock-group";
  final int numInstances = 3;
  final int numPartitions = 12;
  final boolean startController = false;
  HelixManager controllerManager = null;
  Thread[] processArray;
  processArray = new Thread[numInstances];
  try {
    startLocalZookeeper(2199);
    HelixAdmin admin = new ZKHelixAdmin(zkAddress);
    admin.addCluster(clusterName, true);
    StateModelConfigGenerator generator = new StateModelConfigGenerator();
    admin.addStateModelDef(clusterName, "OnlineOffline",
        new StateModelDefinition(generator.generateConfigForOnlineOffline()));
    admin.addResource(clusterName, lockGroupName, numPartitions, "OnlineOffline",
        RebalanceMode.FULL_AUTO.toString());
    admin.rebalance(clusterName, lockGroupName, 1);
    for (int i = 0; i < numInstances; i++) {
      final String instanceName = "localhost_" + (12000 + i);
      processArray[i] = new Thread(new Runnable() {

        @Override
        public void run() {
          LockProcess lockProcess = null;

          try {
            lockProcess = new LockProcess(clusterName, zkAddress, instanceName, startController);
            lockProcess.start();
            Thread.currentThread().join();
          } catch (InterruptedException e) {
            System.out.println(instanceName + "Interrupted");
            if (lockProcess != null) {
              lockProcess.stop();
            }
          } catch (Exception e) {
            e.printStackTrace();
          }
        }

      });
      processArray[i].start();
    }
    Thread.sleep(3000);
    controllerManager =
        HelixControllerMain.startHelixController(zkAddress, clusterName, "controller",
            HelixControllerMain.STANDALONE);
    Thread.sleep(5000);
    printStatus(admin, clusterName, lockGroupName);
    System.out.println("Stopping localhost_12000");
    processArray[0].interrupt();
    Thread.sleep(3000);
    printStatus(admin, clusterName, lockGroupName);
    Thread.currentThread().join();
  } catch (Exception e) {
    e.printStackTrace();
  } finally {
    if (controllerManager != null) {
      controllerManager.disconnect();
    }
    for (Thread process : processArray) {
      if (process != null) {
        process.interrupt();
      }
    }
  }
}