| /** |
| * 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.balancer; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.hdfs.protocol.DatanodeInfo; |
| |
| /** |
| * Balancing policy. |
| * Since a datanode may contain multiple block pools, |
| * {@link Pool} implies {@link Node} |
| * but NOT the other way around |
| */ |
| @InterfaceAudience.Private |
| abstract class BalancingPolicy { |
| long totalCapacity; |
| long totalUsedSpace; |
| private double avgUtilization; |
| |
| void reset() { |
| totalCapacity = 0L; |
| totalUsedSpace = 0L; |
| avgUtilization = 0.0; |
| } |
| |
| /** Get the policy name. */ |
| abstract String getName(); |
| |
| /** Accumulate used space and capacity. */ |
| abstract void accumulateSpaces(DatanodeInfo d); |
| |
| void initAvgUtilization() { |
| this.avgUtilization = totalUsedSpace*100.0/totalCapacity; |
| } |
| double getAvgUtilization() { |
| return avgUtilization; |
| } |
| |
| /** Return the utilization of a datanode */ |
| abstract double getUtilization(DatanodeInfo d); |
| |
| @Override |
| public String toString() { |
| return BalancingPolicy.class.getSimpleName() |
| + "." + getClass().getSimpleName(); |
| } |
| |
| /** Get all {@link BalancingPolicy} instances*/ |
| static BalancingPolicy parse(String s) { |
| final BalancingPolicy [] all = {BalancingPolicy.Node.INSTANCE, |
| BalancingPolicy.Pool.INSTANCE}; |
| for(BalancingPolicy p : all) { |
| if (p.getName().equalsIgnoreCase(s)) |
| return p; |
| } |
| throw new IllegalArgumentException("Cannot parse string \"" + s + "\""); |
| } |
| |
| /** |
| * Cluster is balanced if each node is balanced. |
| */ |
| static class Node extends BalancingPolicy { |
| static Node INSTANCE = new Node(); |
| private Node() {} |
| |
| @Override |
| String getName() { |
| return "datanode"; |
| } |
| |
| @Override |
| void accumulateSpaces(DatanodeInfo d) { |
| totalCapacity += d.getCapacity(); |
| totalUsedSpace += d.getDfsUsed(); |
| } |
| |
| @Override |
| double getUtilization(DatanodeInfo d) { |
| return d.getDfsUsed()*100.0/d.getCapacity(); |
| } |
| } |
| |
| /** |
| * Cluster is balanced if each pool in each node is balanced. |
| */ |
| static class Pool extends BalancingPolicy { |
| static Pool INSTANCE = new Pool(); |
| private Pool() {} |
| |
| @Override |
| String getName() { |
| return "blockpool"; |
| } |
| |
| @Override |
| void accumulateSpaces(DatanodeInfo d) { |
| totalCapacity += d.getCapacity(); |
| totalUsedSpace += d.getBlockPoolUsed(); |
| } |
| |
| @Override |
| double getUtilization(DatanodeInfo d) { |
| return d.getBlockPoolUsed()*100.0/d.getCapacity(); |
| } |
| } |
| } |