| /* |
| * 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.iotdb.confignode.manager.load.balancer.region; |
| |
| import org.apache.iotdb.common.rpc.thrift.TConsensusGroupId; |
| import org.apache.iotdb.common.rpc.thrift.TDataNodeConfiguration; |
| import org.apache.iotdb.common.rpc.thrift.TDataNodeLocation; |
| import org.apache.iotdb.common.rpc.thrift.TRegionReplicaSet; |
| |
| import org.apache.tsfile.utils.Pair; |
| |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.stream.Collectors; |
| |
| import static java.util.Map.Entry.comparingByValue; |
| |
| /** Allocate Region Greedily */ |
| public class GreedyRegionGroupAllocator implements IRegionGroupAllocator { |
| |
| public GreedyRegionGroupAllocator() { |
| // Empty constructor |
| } |
| |
| @Override |
| public TRegionReplicaSet generateOptimalRegionReplicasDistribution( |
| Map<Integer, TDataNodeConfiguration> availableDataNodeMap, |
| Map<Integer, Double> freeDiskSpaceMap, |
| List<TRegionReplicaSet> allocatedRegionGroups, |
| List<TRegionReplicaSet> databaseAllocatedRegionGroups, |
| int replicationFactor, |
| TConsensusGroupId consensusGroupId) { |
| // Build weightList order by number of regions allocated asc |
| List<TDataNodeLocation> weightList = |
| buildWeightList(availableDataNodeMap, freeDiskSpaceMap, allocatedRegionGroups); |
| return new TRegionReplicaSet( |
| consensusGroupId, |
| weightList.stream().limit(replicationFactor).collect(Collectors.toList())); |
| } |
| |
| private List<TDataNodeLocation> buildWeightList( |
| Map<Integer, TDataNodeConfiguration> availableDataNodeMap, |
| Map<Integer, Double> freeDiskSpaceMap, |
| List<TRegionReplicaSet> allocatedRegionGroups) { |
| |
| // Map<DataNodeId, Region count> |
| Map<Integer, Integer> regionCounter = new HashMap<>(availableDataNodeMap.size()); |
| allocatedRegionGroups.forEach( |
| regionReplicaSet -> |
| regionReplicaSet |
| .getDataNodeLocations() |
| .forEach( |
| dataNodeLocation -> |
| regionCounter.merge(dataNodeLocation.getDataNodeId(), 1, Integer::sum))); |
| |
| /* Construct priority map */ |
| Map<TDataNodeLocation, Pair<Integer, Double>> priorityMap = |
| new HashMap<>(availableDataNodeMap.size()); |
| availableDataNodeMap.forEach( |
| (datanodeId, dataNodeConfiguration) -> |
| priorityMap.put( |
| dataNodeConfiguration.getLocation(), |
| new Pair<>( |
| regionCounter.getOrDefault(datanodeId, 0), |
| freeDiskSpaceMap.getOrDefault(datanodeId, 0d)))); |
| |
| // Sort weightList |
| return priorityMap.entrySet().stream() |
| .sorted( |
| comparingByValue( |
| (o1, o2) -> |
| !Objects.equals(o1.getLeft(), o2.getLeft()) |
| // Compare the first key(The number of Regions) by ascending order |
| ? o1.getLeft() - o2.getLeft() |
| // Compare the second key(The free disk space) by descending order |
| : (int) (o2.getRight() - o1.getRight()))) |
| .map(entry -> entry.getKey().deepCopy()) |
| .collect(Collectors.toList()); |
| } |
| } |