| /** |
| * 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.blockmanagement; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.concurrent.atomic.AtomicLong; |
| |
| import org.apache.hadoop.hdfs.server.namenode.NameNode; |
| import org.apache.hadoop.hdfs.util.LightWeightHashSet; |
| import org.slf4j.Logger; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| |
| /** |
| * Maps a datnode to the set of excess redundancy details. |
| * |
| * This class is thread safe. |
| */ |
| class ExcessRedundancyMap { |
| public static final Logger blockLog = NameNode.blockStateChangeLog; |
| |
| private final Map<String, LightWeightHashSet<BlockInfo>> map =new HashMap<>(); |
| private final AtomicLong size = new AtomicLong(0L); |
| |
| /** |
| * @return the number of redundancies in this map. |
| */ |
| long size() { |
| return size.get(); |
| } |
| |
| /** |
| * @return the number of redundancies corresponding to the given datanode. |
| */ |
| @VisibleForTesting |
| synchronized int getSize4Testing(String dnUuid) { |
| final LightWeightHashSet<BlockInfo> set = map.get(dnUuid); |
| return set == null? 0: set.size(); |
| } |
| |
| synchronized void clear() { |
| map.clear(); |
| size.set(0L); |
| } |
| |
| /** |
| * @return does this map contains a redundancy corresponding to the given |
| * datanode and the given block? |
| */ |
| synchronized boolean contains(DatanodeDescriptor dn, BlockInfo blk) { |
| final LightWeightHashSet<BlockInfo> set = map.get(dn.getDatanodeUuid()); |
| return set != null && set.contains(blk); |
| } |
| |
| /** |
| * Add the redundancy of the given block stored in the given datanode to the |
| * map. |
| * |
| * @return true if the block is added. |
| */ |
| synchronized boolean add(DatanodeDescriptor dn, BlockInfo blk) { |
| LightWeightHashSet<BlockInfo> set = map.get(dn.getDatanodeUuid()); |
| if (set == null) { |
| set = new LightWeightHashSet<>(); |
| map.put(dn.getDatanodeUuid(), set); |
| } |
| final boolean added = set.add(blk); |
| if (added) { |
| size.incrementAndGet(); |
| blockLog.debug("BLOCK* ExcessRedundancyMap.add({}, {})", dn, blk); |
| } |
| return added; |
| } |
| |
| /** |
| * Remove the redundancy corresponding to the given datanode and the given |
| * block. |
| * |
| * @return true if the block is removed. |
| */ |
| synchronized boolean remove(DatanodeDescriptor dn, BlockInfo blk) { |
| final LightWeightHashSet<BlockInfo> set = map.get(dn.getDatanodeUuid()); |
| if (set == null) { |
| return false; |
| } |
| |
| final boolean removed = set.remove(blk); |
| if (removed) { |
| size.decrementAndGet(); |
| blockLog.debug("BLOCK* ExcessRedundancyMap.remove({}, {})", dn, blk); |
| |
| if (set.isEmpty()) { |
| map.remove(dn.getDatanodeUuid()); |
| } |
| } |
| return removed; |
| } |
| } |