hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/metrics/ECBlockGroupsMBean.java

/**
 * 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.hdfs.server.namenode.metrics;

import org.apache.hadoop.classification.InterfaceAudience;

/**
 * This interface defines the methods to get status pertaining to blocks of type
 * {@link org.apache.hadoop.hdfs.protocol.BlockType#STRIPED} in FSNamesystem
 * of a NameNode. It is also used for publishing via JMX.
 * <p>
 * Aggregated status of all blocks is reported in
 * @see FSNamesystemMBean
 * Name Node runtime activity statistic info is reported in
 * @see org.apache.hadoop.hdfs.server.namenode.metrics.NameNodeMetrics
 *
 */
@InterfaceAudience.Private
public interface ECBlockGroupsMBean {
  /**
   * Return count of erasure coded block groups with low redundancy.
   */
  long getLowRedundancyECBlockGroups();

  /**
   * Return count of erasure coded block groups that are corrupt.
   */
  long getCorruptECBlockGroups();

  /**
   * Return count of erasure coded block groups that are missing.
   */
  long getMissingECBlockGroups();

  /**
   * Return total bytes of erasure coded future block groups.
   */
  long getBytesInFutureECBlockGroups();

  /**
   * Return count of erasure coded blocks that are pending deletion.
   */
  long getPendingDeletionECBlocks();

  /**
   * Return total number of erasure coded block groups.
   */
  long getTotalECBlockGroups();

  /**
   * @return the enabled erasure coding policies separated with comma.
   */
  String getEnabledEcPolicies();
}