| /* |
| * 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.hbase.master.balancer; |
| |
| import java.util.Collection; |
| import org.apache.yetus.audience.InterfaceAudience; |
| |
| /** |
| * Class to be used for the subset of RegionLoad costs that should be treated as rates. We do not |
| * compare about the actual rate in requests per second but rather the rate relative to the rest of |
| * the regions. |
| */ |
| @InterfaceAudience.Private |
| abstract class CostFromRegionLoadAsRateFunction extends CostFromRegionLoadFunction { |
| |
| @Override |
| protected double getRegionLoadCost(Collection<BalancerRegionLoad> regionLoadList) { |
| double cost = 0; |
| double previous = 0; |
| boolean isFirst = true; |
| for (BalancerRegionLoad rl : regionLoadList) { |
| double current = getCostFromRl(rl); |
| if (isFirst) { |
| isFirst = false; |
| } else { |
| cost += current - previous; |
| } |
| previous = current; |
| } |
| return Math.max(0, cost / (regionLoadList.size() - 1)); |
| } |
| } |