001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.master.balancer;
019
020import static org.junit.Assert.assertEquals;
021import static org.junit.Assert.assertTrue;
022
023import java.util.ArrayList;
024import java.util.Collections;
025import java.util.HashMap;
026import java.util.HashSet;
027import java.util.Iterator;
028import java.util.List;
029import java.util.Map;
030import java.util.Set;
031import org.apache.commons.lang3.StringUtils;
032import org.apache.hadoop.conf.Configuration;
033import org.apache.hadoop.hbase.HBaseClassTestRule;
034import org.apache.hadoop.hbase.HBaseConfiguration;
035import org.apache.hadoop.hbase.HConstants;
036import org.apache.hadoop.hbase.ServerName;
037import org.apache.hadoop.hbase.TableName;
038import org.apache.hadoop.hbase.client.RegionInfo;
039import org.apache.hadoop.hbase.master.LoadBalancer;
040import org.apache.hadoop.hbase.master.RegionPlan;
041import org.apache.hadoop.hbase.net.Address;
042import org.apache.hadoop.hbase.rsgroup.RSGroupBasedLoadBalancer;
043import org.apache.hadoop.hbase.rsgroup.RSGroupInfo;
044import org.apache.hadoop.hbase.testclassification.LargeTests;
045import org.junit.BeforeClass;
046import org.junit.ClassRule;
047import org.junit.Test;
048import org.junit.experimental.categories.Category;
049import org.slf4j.Logger;
050import org.slf4j.LoggerFactory;
051
052import org.apache.hbase.thirdparty.com.google.common.collect.ArrayListMultimap;
053/**
054 * Test RSGroupBasedLoadBalancer with SimpleLoadBalancer as internal balancer
055 */
056@Category(LargeTests.class)
057public class TestRSGroupBasedLoadBalancer extends RSGroupableBalancerTestBase {
058  @ClassRule
059  public static final HBaseClassTestRule CLASS_RULE =
060      HBaseClassTestRule.forClass(TestRSGroupBasedLoadBalancer.class);
061  private static final Logger LOG = LoggerFactory.getLogger(TestRSGroupBasedLoadBalancer.class);
062  private static RSGroupBasedLoadBalancer loadBalancer;
063
064  @BeforeClass
065  public static void beforeAllTests() throws Exception {
066    servers = generateServers(7);
067    groupMap = constructGroupInfo(servers, groups);
068    tableDescs = constructTableDesc(true);
069    Configuration conf = HBaseConfiguration.create();
070    conf.set("hbase.regions.slop", "0");
071    conf.set("hbase.rsgroup.grouploadbalancer.class", SimpleLoadBalancer.class.getCanonicalName());
072    loadBalancer = new RSGroupBasedLoadBalancer();
073    loadBalancer.setRsGroupInfoManager(getMockedGroupInfoManager());
074    loadBalancer.setMasterServices(getMockedMaster());
075    loadBalancer.setConf(conf);
076    loadBalancer.initialize();
077  }
078
079  /**
080   * Test the load balancing algorithm.
081   *
082   * Invariant is that all servers of the group should be hosting either floor(average) or
083   * ceiling(average)
084   */
085  @Test
086  public void testBalanceCluster() throws Exception {
087    // Test with/without per table balancer.
088    boolean[] perTableBalancerConfigs = { true, false };
089    for (boolean isByTable : perTableBalancerConfigs) {
090      Configuration conf = loadBalancer.getConf();
091      conf.setBoolean(HConstants.HBASE_MASTER_LOADBALANCE_BYTABLE, isByTable);
092      loadBalancer.setConf(conf);
093      Map<ServerName, List<RegionInfo>> servers = mockClusterServers();
094      ArrayListMultimap<String, ServerAndLoad> list = convertToGroupBasedMap(servers);
095      LOG.info("Mock Cluster :  " + printStats(list));
096      Map<TableName, Map<ServerName, List<RegionInfo>>> LoadOfAllTable =
097          (Map) mockClusterServersWithTables(servers);
098      List<RegionPlan> plans = loadBalancer.balanceCluster(LoadOfAllTable);
099      ArrayListMultimap<String, ServerAndLoad> balancedCluster = reconcile(list, plans);
100      LOG.info("Mock Balance : " + printStats(balancedCluster));
101      assertClusterAsBalanced(balancedCluster);
102    }
103  }
104
105  /**
106   * Tests the bulk assignment used during cluster startup.
107   *
108   * Round-robin. Should yield a balanced cluster so same invariant as the
109   * load balancer holds, all servers holding either floor(avg) or
110   * ceiling(avg).
111   */
112  @Test
113  public void testBulkAssignment() throws Exception {
114    List<RegionInfo> regions = randomRegions(25);
115    Map<ServerName, List<RegionInfo>> assignments = loadBalancer
116        .roundRobinAssignment(regions, servers);
117    //test empty region/servers scenario
118    //this should not throw an NPE
119    loadBalancer.roundRobinAssignment(regions, Collections.emptyList());
120    //test regular scenario
121    assertTrue(assignments.keySet().size() == servers.size());
122    for (ServerName sn : assignments.keySet()) {
123      List<RegionInfo> regionAssigned = assignments.get(sn);
124      for (RegionInfo region : regionAssigned) {
125        TableName tableName = region.getTable();
126        String groupName =
127            getMockedGroupInfoManager().getRSGroupOfTable(tableName);
128        assertTrue(StringUtils.isNotEmpty(groupName));
129        RSGroupInfo gInfo = getMockedGroupInfoManager().getRSGroup(
130            groupName);
131        assertTrue(
132            "Region is not correctly assigned to group servers.",
133            gInfo.containsServer(sn.getAddress()));
134      }
135    }
136    ArrayListMultimap<String, ServerAndLoad> loadMap = convertToGroupBasedMap(assignments);
137    assertClusterAsBalanced(loadMap);
138  }
139
140  /**
141   * Test the cluster startup bulk assignment which attempts to retain assignment info.
142   */
143  @Test
144  public void testRetainAssignment() throws Exception {
145    // Test simple case where all same servers are there
146    Map<ServerName, List<RegionInfo>> currentAssignments = mockClusterServers();
147    Map<RegionInfo, ServerName> inputForTest = new HashMap<>();
148    for (ServerName sn : currentAssignments.keySet()) {
149      for (RegionInfo region : currentAssignments.get(sn)) {
150        inputForTest.put(region, sn);
151      }
152    }
153    //verify region->null server assignment is handled
154    inputForTest.put(randomRegions(1).get(0), null);
155    Map<ServerName, List<RegionInfo>> newAssignment = loadBalancer
156        .retainAssignment(inputForTest, servers);
157    assertRetainedAssignment(inputForTest, servers, newAssignment);
158  }
159
160  /**
161   * Test BOGUS_SERVER_NAME among groups do not overwrite each other.
162   */
163  @Test
164  public void testRoundRobinAssignment() throws Exception {
165    List<ServerName> onlineServers = new ArrayList<ServerName>(servers.size());
166    onlineServers.addAll(servers);
167    List<RegionInfo> regions = randomRegions(25);
168    int bogusRegion = 0;
169    for(RegionInfo region : regions){
170      String group = tableMap.get(region.getTable());
171      if("dg3".equals(group) || "dg4".equals(group)){
172        bogusRegion++;
173      }
174    }
175    Set<Address> offlineServers = new HashSet<Address>();
176    offlineServers.addAll(groupMap.get("dg3").getServers());
177    offlineServers.addAll(groupMap.get("dg4").getServers());
178    for(Iterator<ServerName> it =  onlineServers.iterator(); it.hasNext();){
179      ServerName server = it.next();
180      Address address = server.getAddress();
181      if(offlineServers.contains(address)){
182        it.remove();
183      }
184    }
185    Map<ServerName, List<RegionInfo>> assignments = loadBalancer
186        .roundRobinAssignment(regions, onlineServers);
187    assertEquals(bogusRegion, assignments.get(LoadBalancer.BOGUS_SERVER_NAME).size());
188  }
189}