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.apache.hadoop.hbase.ServerName.NON_STARTCODE;
021import static org.junit.Assert.assertEquals;
022import static org.junit.Assert.assertFalse;
023import static org.junit.Assert.assertNotNull;
024import static org.junit.Assert.assertNull;
025import static org.junit.Assert.assertTrue;
026
027import java.io.IOException;
028import java.util.EnumSet;
029import java.util.List;
030import java.util.Map;
031import java.util.Map.Entry;
032import java.util.Set;
033import java.util.stream.Collectors;
034import org.apache.hadoop.conf.Configuration;
035import org.apache.hadoop.hbase.ClusterMetrics.Option;
036import org.apache.hadoop.hbase.HBaseClassTestRule;
037import org.apache.hadoop.hbase.HBaseTestingUtil;
038import org.apache.hadoop.hbase.HConstants;
039import org.apache.hadoop.hbase.ServerName;
040import org.apache.hadoop.hbase.SingleProcessHBaseCluster;
041import org.apache.hadoop.hbase.TableName;
042import org.apache.hadoop.hbase.Waiter;
043import org.apache.hadoop.hbase.client.Admin;
044import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
045import org.apache.hadoop.hbase.client.RegionInfo;
046import org.apache.hadoop.hbase.client.TableDescriptor;
047import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
048import org.apache.hadoop.hbase.favored.FavoredNodeAssignmentHelper;
049import org.apache.hadoop.hbase.favored.FavoredNodesManager;
050import org.apache.hadoop.hbase.favored.FavoredNodesPlan;
051import org.apache.hadoop.hbase.master.HMaster;
052import org.apache.hadoop.hbase.master.LoadBalancer;
053import org.apache.hadoop.hbase.master.ServerManager;
054import org.apache.hadoop.hbase.master.assignment.RegionStateNode;
055import org.apache.hadoop.hbase.master.assignment.RegionStates;
056import org.apache.hadoop.hbase.regionserver.HRegion;
057import org.apache.hadoop.hbase.testclassification.MediumTests;
058import org.apache.hadoop.hbase.util.Bytes;
059import org.apache.hadoop.hbase.util.JVMClusterUtil;
060import org.junit.After;
061import org.junit.Before;
062import org.junit.BeforeClass;
063import org.junit.ClassRule;
064import org.junit.Ignore;
065import org.junit.Test;
066import org.junit.experimental.categories.Category;
067import org.slf4j.Logger;
068import org.slf4j.LoggerFactory;
069
070import org.apache.hbase.thirdparty.com.google.common.collect.Lists;
071import org.apache.hbase.thirdparty.com.google.common.collect.Maps;
072import org.apache.hbase.thirdparty.com.google.common.collect.Sets;
073
074@Ignore // Disabled
075@Category(MediumTests.class)
076public class TestFavoredStochasticLoadBalancer extends BalancerTestBase {
077
078  @ClassRule
079  public static final HBaseClassTestRule CLASS_RULE =
080    HBaseClassTestRule.forClass(TestFavoredStochasticLoadBalancer.class);
081
082  private static final Logger LOG =
083    LoggerFactory.getLogger(TestFavoredStochasticLoadBalancer.class);
084
085  private static final HBaseTestingUtil TEST_UTIL = new HBaseTestingUtil();
086  private static final int SLAVES = 8;
087  private static final int REGION_NUM = SLAVES * 3;
088
089  private Admin admin;
090  private HMaster master;
091  private SingleProcessHBaseCluster cluster;
092
093  @BeforeClass
094  public static void setupBeforeClass() throws Exception {
095    Configuration conf = TEST_UTIL.getConfiguration();
096    // Enable the favored nodes based load balancer
097    conf.setClass(HConstants.HBASE_MASTER_LOADBALANCER_CLASS,
098      LoadOnlyFavoredStochasticBalancer.class, LoadBalancer.class);
099  }
100
101  @Before
102  public void startCluster() throws Exception {
103    TEST_UTIL.startMiniCluster(SLAVES);
104    TEST_UTIL.getDFSCluster().waitClusterUp();
105    cluster = TEST_UTIL.getMiniHBaseCluster();
106    master = TEST_UTIL.getMiniHBaseCluster().getMaster();
107    admin = TEST_UTIL.getAdmin();
108    admin.balancerSwitch(false, true);
109  }
110
111  @After
112  public void stopCluster() throws Exception {
113    TEST_UTIL.cleanupTestDir();
114    TEST_UTIL.shutdownMiniCluster();
115  }
116
117  @Test
118  public void testBasicBalance() throws Exception {
119
120    TableName tableName = TableName.valueOf("testBasicBalance");
121    TableDescriptor tableDescriptor = TableDescriptorBuilder.newBuilder(tableName)
122      .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
123    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
124    TEST_UTIL.waitTableAvailable(tableName);
125    TEST_UTIL.loadTable(admin.getConnection().getTable(tableName), HConstants.CATALOG_FAMILY);
126    admin.flush(tableName);
127    compactTable(tableName);
128
129    JVMClusterUtil.RegionServerThread rs1 = cluster.startRegionServerAndWait(10000);
130    JVMClusterUtil.RegionServerThread rs2 = cluster.startRegionServerAndWait(10000);
131
132    // Now try to run balance, and verify no regions are moved to the 2 region servers recently
133    // started.
134    admin.balancerSwitch(true, true);
135    assertTrue("Balancer did not run", admin.balance());
136    TEST_UTIL.waitUntilNoRegionsInTransition(120000);
137
138    List<RegionInfo> hris = admin.getRegions(rs1.getRegionServer().getServerName());
139    for (RegionInfo hri : hris) {
140      assertFalse("New RS contains regions belonging to table: " + tableName,
141        hri.getTable().equals(tableName));
142    }
143    hris = admin.getRegions(rs2.getRegionServer().getServerName());
144    for (RegionInfo hri : hris) {
145      assertFalse("New RS contains regions belonging to table: " + tableName,
146        hri.getTable().equals(tableName));
147    }
148  }
149
150  @Test
151  public void testRoundRobinAssignment() throws Exception {
152
153    TableName tableName = TableName.valueOf("testRoundRobinAssignment");
154    TableDescriptor tableDescriptor = TableDescriptorBuilder.newBuilder(tableName)
155      .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
156    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
157    TEST_UTIL.waitTableAvailable(tableName);
158    TEST_UTIL.loadTable(admin.getConnection().getTable(tableName), HConstants.CATALOG_FAMILY);
159    admin.flush(tableName);
160
161    LoadBalancer balancer = master.getLoadBalancer();
162    List<RegionInfo> regions = admin.getRegions(tableName);
163    regions.addAll(admin.getRegions(TableName.META_TABLE_NAME));
164    List<ServerName> servers = Lists.newArrayList(
165      admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS)).getLiveServerMetrics().keySet());
166    Map<ServerName, List<RegionInfo>> map = balancer.roundRobinAssignment(regions, servers);
167    for (List<RegionInfo> regionInfos : map.values()) {
168      regions.removeAll(regionInfos);
169    }
170    assertEquals("No region should be missed by balancer", 0, regions.size());
171  }
172
173  @Test
174  public void testBasicRegionPlacementAndReplicaLoad() throws Exception {
175    String tableName = "testBasicRegionPlacement";
176    TableDescriptor tableDescriptor =
177      TableDescriptorBuilder.newBuilder(TableName.valueOf(tableName))
178        .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
179    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
180    TEST_UTIL.waitTableAvailable(tableDescriptor.getTableName());
181
182    FavoredNodesManager fnm = master.getFavoredNodesManager();
183    List<RegionInfo> regionsOfTable = admin.getRegions(TableName.valueOf(tableName));
184    for (RegionInfo rInfo : regionsOfTable) {
185      Set<ServerName> favNodes = Sets.newHashSet(fnm.getFavoredNodes(rInfo));
186      assertNotNull(favNodes);
187      assertEquals(FavoredNodeAssignmentHelper.FAVORED_NODES_NUM, favNodes.size());
188    }
189
190    Map<ServerName, List<Integer>> replicaLoadMap = fnm.getReplicaLoad(Lists.newArrayList(
191      admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS)).getLiveServerMetrics().keySet()));
192    assertTrue("Not all replica load collected.",
193      admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS)).getLiveServerMetrics().size()
194          == replicaLoadMap.size());
195    for (Entry<ServerName, List<Integer>> entry : replicaLoadMap.entrySet()) {
196      assertTrue(entry.getValue().size() == FavoredNodeAssignmentHelper.FAVORED_NODES_NUM);
197      assertTrue(entry.getValue().get(0) >= 0);
198      assertTrue(entry.getValue().get(1) >= 0);
199      assertTrue(entry.getValue().get(2) >= 0);
200    }
201
202    admin.disableTable(TableName.valueOf(tableName));
203    admin.deleteTable(TableName.valueOf(tableName));
204    replicaLoadMap = fnm.getReplicaLoad(Lists.newArrayList(
205      admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS)).getLiveServerMetrics().keySet()));
206    assertTrue("replica load found " + replicaLoadMap.size() + " instead of 0.",
207      replicaLoadMap.size() == admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS))
208        .getLiveServerMetrics().size());
209  }
210
211  @Test
212  public void testRandomAssignmentWithNoFavNodes() throws Exception {
213
214    final String tableName = "testRandomAssignmentWithNoFavNodes";
215    TableDescriptor tableDescriptor =
216      TableDescriptorBuilder.newBuilder(TableName.valueOf(tableName))
217        .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
218    admin.createTable(tableDescriptor);
219    TEST_UTIL.waitTableAvailable(tableDescriptor.getTableName());
220
221    RegionInfo hri = admin.getRegions(TableName.valueOf(tableName)).get(0);
222
223    FavoredNodesManager fnm = master.getFavoredNodesManager();
224    fnm.deleteFavoredNodesForRegions(Lists.newArrayList(hri));
225    assertNull("Favored nodes not found null after delete", fnm.getFavoredNodes(hri));
226
227    LoadBalancer balancer = master.getLoadBalancer();
228    ServerName destination = balancer.randomAssignment(hri,
229      Lists.newArrayList(admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS))
230        .getLiveServerMetrics().keySet().stream().collect(Collectors.toList())));
231    assertNotNull(destination);
232    List<ServerName> favoredNodes = fnm.getFavoredNodes(hri);
233    assertNotNull(favoredNodes);
234    boolean containsFN = false;
235    for (ServerName sn : favoredNodes) {
236      if (ServerName.isSameAddress(destination, sn)) {
237        containsFN = true;
238      }
239    }
240    assertTrue("Destination server does not belong to favored nodes.", containsFN);
241  }
242
243  @Test
244  public void testBalancerWithoutFavoredNodes() throws Exception {
245
246    TableName tableName = TableName.valueOf("testBalancerWithoutFavoredNodes");
247    TableDescriptor tableDescriptor = TableDescriptorBuilder.newBuilder(tableName)
248      .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
249    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
250    TEST_UTIL.waitTableAvailable(tableName);
251
252    final RegionInfo region = admin.getRegions(tableName).get(0);
253    LOG.info("Region thats supposed to be in transition: " + region);
254    FavoredNodesManager fnm = master.getFavoredNodesManager();
255    List<ServerName> currentFN = fnm.getFavoredNodes(region);
256    assertNotNull(currentFN);
257
258    fnm.deleteFavoredNodesForRegions(Lists.newArrayList(region));
259
260    RegionStates regionStates = master.getAssignmentManager().getRegionStates();
261    admin.balancerSwitch(true, true);
262
263    // Balancer should unassign the region
264    assertTrue("Balancer did not run", admin.balance());
265    TEST_UTIL.waitUntilNoRegionsInTransition();
266
267    admin.assign(region.getEncodedNameAsBytes());
268    TEST_UTIL.waitUntilNoRegionsInTransition(60000);
269
270    currentFN = fnm.getFavoredNodes(region);
271    assertNotNull(currentFN);
272    assertEquals("Expected number of FN not present", FavoredNodeAssignmentHelper.FAVORED_NODES_NUM,
273      currentFN.size());
274
275    assertTrue("Balancer did not run", admin.balance());
276    TEST_UTIL.waitUntilNoRegionsInTransition(60000);
277
278    checkFavoredNodeAssignments(tableName, fnm, regionStates);
279  }
280
281  @Ignore
282  @Test
283  public void testMisplacedRegions() throws Exception {
284    TableName tableName = TableName.valueOf("testMisplacedRegions");
285    TableDescriptor tableDescriptor = TableDescriptorBuilder.newBuilder(tableName)
286      .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
287    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
288    TEST_UTIL.waitTableAvailable(tableName);
289
290    final RegionInfo misplacedRegion = admin.getRegions(tableName).get(0);
291    FavoredNodesManager fnm = master.getFavoredNodesManager();
292    List<ServerName> currentFN = fnm.getFavoredNodes(misplacedRegion);
293    assertNotNull(currentFN);
294
295    List<ServerName> serversForNewFN = Lists.newArrayList();
296    for (ServerName sn : admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS))
297      .getLiveServerMetrics().keySet()) {
298      serversForNewFN.add(ServerName.valueOf(sn.getHostname(), sn.getPort(), NON_STARTCODE));
299    }
300    for (ServerName sn : currentFN) {
301      serversForNewFN.remove(sn);
302    }
303    FavoredNodeAssignmentHelper helper = new FavoredNodeAssignmentHelper(serversForNewFN, conf);
304    helper.initialize();
305    List<ServerName> newFavoredNodes = helper.generateFavoredNodes(misplacedRegion);
306    assertNotNull(newFavoredNodes);
307    assertEquals(FavoredNodeAssignmentHelper.FAVORED_NODES_NUM, newFavoredNodes.size());
308    Map<RegionInfo, List<ServerName>> regionFNMap = Maps.newHashMap();
309    regionFNMap.put(misplacedRegion, newFavoredNodes);
310    fnm.updateFavoredNodes(regionFNMap);
311
312    final RegionStates regionStates = master.getAssignmentManager().getRegionStates();
313    final ServerName current = regionStates.getRegionServerOfRegion(misplacedRegion);
314    assertNull("Misplaced region is still hosted on favored node, not expected.",
315      FavoredNodesPlan.getFavoredServerPosition(fnm.getFavoredNodes(misplacedRegion), current));
316    admin.balancerSwitch(true, true);
317    assertTrue("Balancer did not run", admin.balance());
318    TEST_UTIL.waitFor(120000, 30000, new Waiter.Predicate<Exception>() {
319      @Override
320      public boolean evaluate() throws Exception {
321        ServerName host = regionStates.getRegionServerOfRegion(misplacedRegion);
322        return !ServerName.isSameAddress(host, current);
323      }
324    });
325    checkFavoredNodeAssignments(tableName, fnm, regionStates);
326  }
327
328  @Test
329  public void test2FavoredNodesDead() throws Exception {
330    TableName tableName = TableName.valueOf("testAllFavoredNodesDead");
331    TableDescriptor tableDescriptor = TableDescriptorBuilder.newBuilder(tableName)
332      .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
333    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
334    TEST_UTIL.waitTableAvailable(tableName);
335
336    final RegionInfo region = admin.getRegions(tableName).get(0);
337    LOG.info("Region that's supposed to be in transition: " + region);
338    FavoredNodesManager fnm = master.getFavoredNodesManager();
339    List<ServerName> currentFN = fnm.getFavoredNodes(region);
340    assertNotNull(currentFN);
341
342    List<ServerName> serversToStop = Lists.newArrayList(currentFN);
343    serversToStop.remove(currentFN.get(0));
344
345    // Lets kill 2 FN for the region. All regions should still be assigned
346    stopServersAndWaitUntilProcessed(serversToStop);
347
348    TEST_UTIL.waitUntilNoRegionsInTransition();
349    final RegionStates regionStates = master.getAssignmentManager().getRegionStates();
350    TEST_UTIL.waitFor(10000, new Waiter.Predicate<Exception>() {
351      @Override
352      public boolean evaluate() throws Exception {
353        return regionStates.getRegionState(region).isOpened();
354      }
355    });
356
357    assertEquals("Not all regions are online", REGION_NUM, admin.getRegions(tableName).size());
358    admin.balancerSwitch(true, true);
359    assertTrue("Balancer did not run", admin.balance());
360    TEST_UTIL.waitUntilNoRegionsInTransition(60000);
361
362    checkFavoredNodeAssignments(tableName, fnm, regionStates);
363  }
364
365  @Ignore
366  @Test
367  public void testAllFavoredNodesDead() throws Exception {
368    TableName tableName = TableName.valueOf("testAllFavoredNodesDead");
369    TableDescriptor tableDescriptor = TableDescriptorBuilder.newBuilder(tableName)
370      .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
371    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
372    TEST_UTIL.waitTableAvailable(tableName);
373
374    final RegionInfo region = admin.getRegions(tableName).get(0);
375    LOG.info("Region that's supposed to be in transition: " + region);
376    FavoredNodesManager fnm = master.getFavoredNodesManager();
377    List<ServerName> currentFN = fnm.getFavoredNodes(region);
378    assertNotNull(currentFN);
379
380    // Lets kill all the RS that are favored nodes for this region.
381    stopServersAndWaitUntilProcessed(currentFN);
382
383    final RegionStates regionStates = master.getAssignmentManager().getRegionStates();
384    TEST_UTIL.waitFor(10000, new Waiter.Predicate<Exception>() {
385      @Override
386      public boolean evaluate() throws Exception {
387        return regionStates.getRegionState(region).isFailedOpen();
388      }
389    });
390
391    assertTrue("Region: " + region + " should be RIT",
392      regionStates.getRegionState(region).isFailedOpen());
393
394    // Regenerate FN and assign, everything else should be fine
395    List<ServerName> serversForNewFN = Lists.newArrayList();
396    for (ServerName sn : admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS))
397      .getLiveServerMetrics().keySet()) {
398      serversForNewFN.add(ServerName.valueOf(sn.getHostname(), sn.getPort(), NON_STARTCODE));
399    }
400
401    FavoredNodeAssignmentHelper helper = new FavoredNodeAssignmentHelper(serversForNewFN, conf);
402    helper.initialize();
403
404    for (RegionStateNode regionState : regionStates.getRegionsInTransition()) {
405      RegionInfo regionInfo = regionState.getRegionInfo();
406      List<ServerName> newFavoredNodes = helper.generateFavoredNodes(regionInfo);
407      assertNotNull(newFavoredNodes);
408      assertEquals(FavoredNodeAssignmentHelper.FAVORED_NODES_NUM, newFavoredNodes.size());
409      LOG.info("Region: " + regionInfo.getEncodedName() + " FN: " + newFavoredNodes);
410
411      Map<RegionInfo, List<ServerName>> regionFNMap = Maps.newHashMap();
412      regionFNMap.put(regionInfo, newFavoredNodes);
413      fnm.updateFavoredNodes(regionFNMap);
414      LOG.info("Assigning region: " + regionInfo.getEncodedName());
415      admin.assign(regionInfo.getEncodedNameAsBytes());
416    }
417    TEST_UTIL.waitUntilNoRegionsInTransition(60000);
418    assertEquals("Not all regions are online", REGION_NUM, admin.getRegions(tableName).size());
419
420    admin.balancerSwitch(true, true);
421    assertTrue("Balancer did not run", admin.balance());
422    TEST_UTIL.waitUntilNoRegionsInTransition(60000);
423
424    checkFavoredNodeAssignments(tableName, fnm, regionStates);
425  }
426
427  @Ignore
428  @Test
429  public void testAllFavoredNodesDeadMasterRestarted() throws Exception {
430    TableName tableName = TableName.valueOf("testAllFavoredNodesDeadMasterRestarted");
431    TableDescriptor tableDescriptor = TableDescriptorBuilder.newBuilder(tableName)
432      .setColumnFamily(ColumnFamilyDescriptorBuilder.of(HConstants.CATALOG_FAMILY)).build();
433    admin.createTable(tableDescriptor, Bytes.toBytes("aaa"), Bytes.toBytes("zzz"), REGION_NUM);
434    TEST_UTIL.waitTableAvailable(tableName);
435
436    final RegionInfo region = admin.getRegions(tableName).get(0);
437    LOG.info("Region that's supposed to be in transition: " + region);
438    FavoredNodesManager fnm = master.getFavoredNodesManager();
439    List<ServerName> currentFN = fnm.getFavoredNodes(region);
440    assertNotNull(currentFN);
441
442    // Lets kill all the RS that are favored nodes for this region.
443    stopServersAndWaitUntilProcessed(currentFN);
444
445    final RegionStates regionStatesBeforeMaster = master.getAssignmentManager().getRegionStates();
446    TEST_UTIL.waitFor(10000, new Waiter.Predicate<Exception>() {
447      @Override
448      public boolean evaluate() throws Exception {
449        return regionStatesBeforeMaster.getRegionState(region).isFailedOpen();
450      }
451    });
452
453    assertTrue("Region: " + region + " should be RIT",
454      regionStatesBeforeMaster.getRegionState(region).isFailedOpen());
455
456    List<RegionInfo> rit = Lists.newArrayList();
457    for (RegionStateNode regionState : regionStatesBeforeMaster.getRegionsInTransition()) {
458      RegionInfo regionInfo = regionState.getRegionInfo();
459      LOG.debug("Region in transition after stopping FN's: " + regionInfo);
460      rit.add(regionInfo);
461      assertTrue("Region: " + regionInfo + " should be RIT",
462        regionStatesBeforeMaster.getRegionState(regionInfo).isFailedOpen());
463      assertEquals("Region: " + regionInfo + " does not belong to table: " + tableName, tableName,
464        regionInfo.getTable());
465    }
466
467    Configuration conf = cluster.getConf();
468    conf.setInt(ServerManager.WAIT_ON_REGIONSERVERS_MINTOSTART,
469      SLAVES - FavoredNodeAssignmentHelper.FAVORED_NODES_NUM);
470
471    cluster.stopMaster(master.getServerName());
472    cluster.waitForMasterToStop(master.getServerName(), 60000);
473
474    cluster.startMaster();
475    cluster.waitForActiveAndReadyMaster();
476    master = cluster.getMaster();
477    fnm = master.getFavoredNodesManager();
478
479    RegionStates regionStates = master.getAssignmentManager().getRegionStates();
480    assertTrue("Region: " + region + " should be RIT",
481      regionStates.getRegionState(region).isFailedOpen());
482
483    for (RegionInfo regionInfo : rit) {
484      assertTrue("Region: " + regionInfo + " should be RIT",
485        regionStates.getRegionState(regionInfo).isFailedOpen());
486    }
487
488    // Regenerate FN and assign, everything else should be fine
489    List<ServerName> serversForNewFN = Lists.newArrayList();
490    for (ServerName sn : admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS))
491      .getLiveServerMetrics().keySet()) {
492      serversForNewFN.add(ServerName.valueOf(sn.getHostname(), sn.getPort(), NON_STARTCODE));
493    }
494
495    FavoredNodeAssignmentHelper helper = new FavoredNodeAssignmentHelper(serversForNewFN, conf);
496    helper.initialize();
497
498    for (RegionInfo regionInfo : rit) {
499      List<ServerName> newFavoredNodes = helper.generateFavoredNodes(regionInfo);
500      assertNotNull(newFavoredNodes);
501      assertEquals(FavoredNodeAssignmentHelper.FAVORED_NODES_NUM, newFavoredNodes.size());
502      LOG.info("Region: " + regionInfo.getEncodedName() + " FN: " + newFavoredNodes);
503
504      Map<RegionInfo, List<ServerName>> regionFNMap = Maps.newHashMap();
505      regionFNMap.put(regionInfo, newFavoredNodes);
506      fnm.updateFavoredNodes(regionFNMap);
507      LOG.info("Assigning region: " + regionInfo.getEncodedName());
508      admin.assign(regionInfo.getEncodedNameAsBytes());
509    }
510    TEST_UTIL.waitUntilNoRegionsInTransition(60000);
511    assertEquals("Not all regions are online", REGION_NUM, admin.getRegions(tableName).size());
512
513    admin.balancerSwitch(true, true);
514    assertTrue("Balancer did not run", admin.balance());
515    TEST_UTIL.waitUntilNoRegionsInTransition(60000);
516
517    checkFavoredNodeAssignments(tableName, fnm, regionStates);
518  }
519
520  private void checkFavoredNodeAssignments(TableName tableName, FavoredNodesManager fnm,
521    RegionStates regionStates) throws IOException {
522    for (RegionInfo hri : admin.getRegions(tableName)) {
523      ServerName host = regionStates.getRegionServerOfRegion(hri);
524      assertNotNull(
525        "Region: " + hri.getEncodedName() + " not on FN, current: " + host + " FN list: "
526          + fnm.getFavoredNodes(hri),
527        FavoredNodesPlan.getFavoredServerPosition(fnm.getFavoredNodes(hri), host));
528    }
529  }
530
531  private void stopServersAndWaitUntilProcessed(List<ServerName> currentFN) throws Exception {
532    for (ServerName sn : currentFN) {
533      for (JVMClusterUtil.RegionServerThread rst : cluster.getLiveRegionServerThreads()) {
534        if (ServerName.isSameAddress(sn, rst.getRegionServer().getServerName())) {
535          LOG.info("Shutting down server: " + sn);
536          cluster.stopRegionServer(rst.getRegionServer().getServerName());
537          cluster.waitForRegionServerToStop(rst.getRegionServer().getServerName(), 60000);
538        }
539      }
540    }
541
542    // Wait until dead servers are processed.
543    TEST_UTIL.waitFor(60000, new Waiter.Predicate<Exception>() {
544      @Override
545      public boolean evaluate() throws Exception {
546        return !master.getServerManager().areDeadServersInProgress();
547      }
548    });
549
550    assertEquals("Not all servers killed", SLAVES - currentFN.size(),
551      cluster.getLiveRegionServerThreads().size());
552  }
553
554  private void compactTable(TableName tableName) throws IOException {
555    for (JVMClusterUtil.RegionServerThread t : cluster.getRegionServerThreads()) {
556      for (HRegion region : t.getRegionServer().getRegions(tableName)) {
557        region.compact(true);
558      }
559    }
560  }
561}