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/**
* 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
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package org.apache.hadoop.hbase.master.balancer;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import java.util.TimeZone;
import java.util.TreeMap;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.ClusterMetrics;
import org.apache.hadoop.hbase.HBaseClassTestRule;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.RegionMetrics;
import org.apache.hadoop.hbase.ServerMetrics;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.Size;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.RegionInfo;
import org.apache.hadoop.hbase.master.MockNoopMasterServices;
import org.apache.hadoop.hbase.master.RegionPlan;
import org.apache.hadoop.hbase.testclassification.MasterTests;
import org.apache.hadoop.hbase.testclassification.MediumTests;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import org.junit.ClassRule;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.apache.hbase.thirdparty.org.apache.commons.collections4.CollectionUtils;
@Category({ MasterTests.class, MediumTests.class })
public class TestStochasticLoadBalancer extends StochasticBalancerTestBase {
@ClassRule
public static final HBaseClassTestRule CLASS_RULE =
HBaseClassTestRule.forClass(TestStochasticLoadBalancer.class);
private static final String REGION_KEY = "testRegion";
// Mapping of locality test -> expected locality
private float[] expectedLocalities = {1.0f, 0.0f, 0.50f, 0.25f, 1.0f};
/**
* Data set for testLocalityCost:
* [test][0][0] = mapping of server to number of regions it hosts
* [test][region + 1][0] = server that region is hosted on
* [test][region + 1][server + 1] = locality for region on server
*/
private int[][][] clusterRegionLocationMocks = new int[][][]{
// Test 1: each region is entirely on server that hosts it
new int[][]{
new int[]{2, 1, 1},
new int[]{2, 0, 0, 100}, // region 0 is hosted and entirely local on server 2
new int[]{0, 100, 0, 0}, // region 1 is hosted and entirely on server 0
new int[]{0, 100, 0, 0}, // region 2 is hosted and entirely on server 0
new int[]{1, 0, 100, 0}, // region 3 is hosted and entirely on server 1
},
// Test 2: each region is 0% local on the server that hosts it
new int[][]{
new int[]{1, 2, 1},
new int[]{0, 0, 0, 100}, // region 0 is hosted and entirely local on server 2
new int[]{1, 100, 0, 0}, // region 1 is hosted and entirely on server 0
new int[]{1, 100, 0, 0}, // region 2 is hosted and entirely on server 0
new int[]{2, 0, 100, 0}, // region 3 is hosted and entirely on server 1
},
// Test 3: each region is 25% local on the server that hosts it (and 50% locality is possible)
new int[][]{
new int[]{1, 2, 1},
new int[]{0, 25, 0, 50}, // region 0 is hosted and entirely local on server 2
new int[]{1, 50, 25, 0}, // region 1 is hosted and entirely on server 0
new int[]{1, 50, 25, 0}, // region 2 is hosted and entirely on server 0
new int[]{2, 0, 50, 25}, // region 3 is hosted and entirely on server 1
},
// Test 4: each region is 25% local on the server that hosts it (and 100% locality is possible)
new int[][]{
new int[]{1, 2, 1},
new int[]{0, 25, 0, 100}, // region 0 is hosted and entirely local on server 2
new int[]{1, 100, 25, 0}, // region 1 is hosted and entirely on server 0
new int[]{1, 100, 25, 0}, // region 2 is hosted and entirely on server 0
new int[]{2, 0, 100, 25}, // region 3 is hosted and entirely on server 1
},
// Test 5: each region is 75% local on the server that hosts it (and 75% locality is possible
// everywhere)
new int[][]{
new int[]{1, 2, 1},
new int[]{0, 75, 75, 75}, // region 0 is hosted and entirely local on server 2
new int[]{1, 75, 75, 75}, // region 1 is hosted and entirely on server 0
new int[]{1, 75, 75, 75}, // region 2 is hosted and entirely on server 0
new int[]{2, 75, 75, 75}, // region 3 is hosted and entirely on server 1
},
};
private ServerMetrics mockServerMetricsWithCpRequests(ServerName server,
List<RegionInfo> regionsOnServer, long cpRequestCount) {
ServerMetrics serverMetrics = mock(ServerMetrics.class);
Map<byte[], RegionMetrics> regionLoadMap = new TreeMap<>(Bytes.BYTES_COMPARATOR);
for(RegionInfo info : regionsOnServer){
RegionMetrics rl = mock(RegionMetrics.class);
when(rl.getReadRequestCount()).thenReturn(0L);
when(rl.getCpRequestCount()).thenReturn(cpRequestCount);
when(rl.getWriteRequestCount()).thenReturn(0L);
when(rl.getMemStoreSize()).thenReturn(Size.ZERO);
when(rl.getStoreFileSize()).thenReturn(Size.ZERO);
regionLoadMap.put(info.getRegionName(), rl);
}
when(serverMetrics.getRegionMetrics()).thenReturn(regionLoadMap);
return serverMetrics;
}
@Test
public void testCPRequestCost() {
// in order to pass needsBalance judgement
conf.setFloat("hbase.master.balancer.stochastic.cpRequestCost", 10000f);
loadBalancer.setConf(conf);
// mock cluster State
Map<ServerName, List<RegionInfo>> clusterState = new HashMap<ServerName, List<RegionInfo>>();
ServerName serverA = randomServer(3).getServerName();
ServerName serverB = randomServer(3).getServerName();
ServerName serverC = randomServer(3).getServerName();
List<RegionInfo> regionsOnServerA = randomRegions(3);
List<RegionInfo> regionsOnServerB = randomRegions(3);
List<RegionInfo> regionsOnServerC = randomRegions(3);
clusterState.put(serverA, regionsOnServerA);
clusterState.put(serverB, regionsOnServerB);
clusterState.put(serverC, regionsOnServerC);
// mock ClusterMetrics
Map<ServerName, ServerMetrics> serverMetricsMap = new TreeMap<>();
serverMetricsMap.put(serverA, mockServerMetricsWithCpRequests(serverA, regionsOnServerA, 0));
serverMetricsMap.put(serverB, mockServerMetricsWithCpRequests(serverB, regionsOnServerB, 0));
serverMetricsMap.put(serverC, mockServerMetricsWithCpRequests(serverC, regionsOnServerC, 0));
ClusterMetrics clusterStatus = mock(ClusterMetrics.class);
when(clusterStatus.getLiveServerMetrics()).thenReturn(serverMetricsMap);
loadBalancer.setClusterMetrics(clusterStatus);
// CPRequestCostFunction are Rate based, So doing setClusterMetrics again
// this time, regions on serverA with more cpRequestCount load
// serverA : 1000,1000,1000
// serverB : 0,0,0
// serverC : 0,0,0
// so should move two regions from serverA to serverB & serverC
serverMetricsMap = new TreeMap<>();
serverMetricsMap.put(serverA, mockServerMetricsWithCpRequests(serverA, regionsOnServerA, 1000));
serverMetricsMap.put(serverB, mockServerMetricsWithCpRequests(serverB, regionsOnServerB, 0));
serverMetricsMap.put(serverC, mockServerMetricsWithCpRequests(serverC, regionsOnServerC, 0));
clusterStatus = mock(ClusterMetrics.class);
when(clusterStatus.getLiveServerMetrics()).thenReturn(serverMetricsMap);
loadBalancer.setClusterMetrics(clusterStatus);
List<RegionPlan> plans =
loadBalancer.balanceTable(HConstants.ENSEMBLE_TABLE_NAME, clusterState);
Set<RegionInfo> regionsMoveFromServerA = new HashSet<>();
Set<ServerName> targetServers = new HashSet<>();
for (RegionPlan plan : plans) {
if (plan.getSource().equals(serverA)) {
regionsMoveFromServerA.add(plan.getRegionInfo());
targetServers.add(plan.getDestination());
}
}
// should move 2 regions from serverA, one moves to serverB, the other moves to serverC
assertEquals(2, regionsMoveFromServerA.size());
assertEquals(2, targetServers.size());
assertTrue(regionsOnServerA.containsAll(regionsMoveFromServerA));
assertNull(loadBalancer.namedQueueRecorder);
// reset config
conf.setFloat("hbase.master.balancer.stochastic.cpRequestCost", 5f);
loadBalancer.setConf(conf);
}
@Test
public void testKeepRegionLoad() throws Exception {
ServerName sn = ServerName.valueOf("test:8080", 100);
int numClusterStatusToAdd = 20000;
for (int i = 0; i < numClusterStatusToAdd; i++) {
ServerMetrics sl = mock(ServerMetrics.class);
RegionMetrics rl = mock(RegionMetrics.class);
when(rl.getReadRequestCount()).thenReturn(0L);
when(rl.getCpRequestCount()).thenReturn(0L);
when(rl.getWriteRequestCount()).thenReturn(0L);
when(rl.getMemStoreSize()).thenReturn(Size.ZERO);
when(rl.getStoreFileSize()).thenReturn(new Size(i, Size.Unit.MEGABYTE));
Map<byte[], RegionMetrics> regionLoadMap = new TreeMap<>(Bytes.BYTES_COMPARATOR);
regionLoadMap.put(Bytes.toBytes(REGION_KEY), rl);
when(sl.getRegionMetrics()).thenReturn(regionLoadMap);
ClusterMetrics clusterStatus = mock(ClusterMetrics.class);
Map<ServerName, ServerMetrics> serverMetricsMap = new TreeMap<>();
serverMetricsMap.put(sn, sl);
when(clusterStatus.getLiveServerMetrics()).thenReturn(serverMetricsMap);
// when(clusterStatus.getLoad(sn)).thenReturn(sl);
loadBalancer.setClusterMetrics(clusterStatus);
}
String regionNameAsString = RegionInfo.getRegionNameAsString(Bytes.toBytes(REGION_KEY));
assertTrue(loadBalancer.loads.get(regionNameAsString) != null);
assertTrue(loadBalancer.loads.get(regionNameAsString).size() == 15);
assertNull(loadBalancer.namedQueueRecorder);
Queue<BalancerRegionLoad> loads = loadBalancer.loads.get(regionNameAsString);
int i = 0;
while(loads.size() > 0) {
BalancerRegionLoad rl = loads.remove();
assertEquals(i + (numClusterStatusToAdd - 15), rl.getStorefileSizeMB());
i ++;
}
}
@Test
public void testNeedBalance() {
float minCost = conf.getFloat("hbase.master.balancer.stochastic.minCostNeedBalance", 0.05f);
conf.setFloat("hbase.master.balancer.stochastic.minCostNeedBalance", 1.0f);
try {
// Test with/without per table balancer.
boolean[] perTableBalancerConfigs = {true, false};
for (boolean isByTable : perTableBalancerConfigs) {
conf.setBoolean(HConstants.HBASE_MASTER_LOADBALANCE_BYTABLE, isByTable);
loadBalancer.setConf(conf);
for (int[] mockCluster : clusterStateMocks) {
Map<ServerName, List<RegionInfo>> servers = mockClusterServers(mockCluster);
Map<TableName, Map<ServerName, List<RegionInfo>>> LoadOfAllTable =
(Map) mockClusterServersWithTables(servers);
List<RegionPlan> plans = loadBalancer.balanceCluster(LoadOfAllTable);
boolean emptyPlans = plans == null || plans.isEmpty();
assertTrue(emptyPlans || needsBalanceIdleRegion(mockCluster));
}
}
} finally {
// reset config
conf.unset(HConstants.HBASE_MASTER_LOADBALANCE_BYTABLE);
conf.setFloat("hbase.master.balancer.stochastic.minCostNeedBalance", minCost);
loadBalancer.setConf(conf);
}
}
@Test
public void testLocalityCost() throws Exception {
Configuration conf = HBaseConfiguration.create();
MockNoopMasterServices master = new MockNoopMasterServices();
CostFunction
costFunction = new ServerLocalityCostFunction(conf);
for (int test = 0; test < clusterRegionLocationMocks.length; test++) {
int[][] clusterRegionLocations = clusterRegionLocationMocks[test];
MockCluster cluster = new MockCluster(clusterRegionLocations);
costFunction.init(cluster);
double cost = costFunction.cost();
double expected = 1 - expectedLocalities[test];
assertEquals(expected, cost, 0.001);
}
assertNull(loadBalancer.namedQueueRecorder);
}
@Test
public void testMoveCostMultiplier() throws Exception {
Configuration conf = HBaseConfiguration.create();
CostFunction
costFunction = new MoveCostFunction(conf);
BalancerClusterState cluster = mockCluster(clusterStateMocks[0]);
costFunction.init(cluster);
costFunction.cost();
assertEquals(MoveCostFunction.DEFAULT_MOVE_COST,
costFunction.getMultiplier(), 0.01);
// In offpeak hours, the multiplier of move cost should be lower
conf.setInt("hbase.offpeak.start.hour",0);
conf.setInt("hbase.offpeak.end.hour",23);
// Set a fixed time which hour is 15, so it will always in offpeak
// See HBASE-24898 for more info of the calculation here
long deltaFor15 = TimeZone.getDefault().getRawOffset() - 28800000;
long timeFor15 = 1597907081000L - deltaFor15;
EnvironmentEdgeManager.injectEdge(() -> timeFor15);
costFunction = new MoveCostFunction(conf);
costFunction.init(cluster);
costFunction.cost();
assertEquals(MoveCostFunction.DEFAULT_MOVE_COST_OFFPEAK
, costFunction.getMultiplier(), 0.01);
}
@Test
public void testMoveCost() throws Exception {
Configuration conf = HBaseConfiguration.create();
CostFunction
costFunction = new MoveCostFunction(conf);
for (int[] mockCluster : clusterStateMocks) {
BalancerClusterState cluster = mockCluster(mockCluster);
costFunction.init(cluster);
double cost = costFunction.cost();
assertEquals(0.0f, cost, 0.001);
// cluster region number is smaller than maxMoves=600
cluster.setNumRegions(200);
cluster.setNumMovedRegions(10);
cost = costFunction.cost();
assertEquals(0.05f, cost, 0.001);
cluster.setNumMovedRegions(100);
cost = costFunction.cost();
assertEquals(0.5f, cost, 0.001);
cluster.setNumMovedRegions(200);
cost = costFunction.cost();
assertEquals(1.0f, cost, 0.001);
// cluster region number is bigger than maxMoves=2500
cluster.setNumRegions(10000);
cluster.setNumMovedRegions(250);
cost = costFunction.cost();
assertEquals(0.1f, cost, 0.001);
cluster.setNumMovedRegions(1250);
cost = costFunction.cost();
assertEquals(0.5f, cost, 0.001);
cluster.setNumMovedRegions(2500);
cost = costFunction.cost();
assertEquals(1.0f, cost, 0.01);
}
}
@Test
public void testSkewCost() {
Configuration conf = HBaseConfiguration.create();
CostFunction
costFunction = new RegionCountSkewCostFunction(conf);
for (int[] mockCluster : clusterStateMocks) {
costFunction.init(mockCluster(mockCluster));
double cost = costFunction.cost();
assertTrue(cost >= 0);
assertTrue(cost <= 1.01);
}
costFunction.init(mockCluster(new int[]{0, 0, 0, 0, 1}));
assertEquals(0,costFunction.cost(), 0.01);
costFunction.init(mockCluster(new int[]{0, 0, 0, 1, 1}));
assertEquals(0, costFunction.cost(), 0.01);
costFunction.init(mockCluster(new int[]{0, 0, 1, 1, 1}));
assertEquals(0, costFunction.cost(), 0.01);
costFunction.init(mockCluster(new int[]{0, 1, 1, 1, 1}));
assertEquals(0, costFunction.cost(), 0.01);
costFunction.init(mockCluster(new int[]{1, 1, 1, 1, 1}));
assertEquals(0, costFunction.cost(), 0.01);
costFunction.init(mockCluster(new int[]{10000, 0, 0, 0, 0}));
assertEquals(1, costFunction.cost(), 0.01);
}
@Test
public void testCostAfterUndoAction() {
final int runs = 10;
loadBalancer.setConf(conf);
for (int[] mockCluster : clusterStateMocks) {
BalancerClusterState cluster = mockCluster(mockCluster);
loadBalancer.initCosts(cluster);
for (int i = 0; i != runs; ++i) {
final double expectedCost = loadBalancer.computeCost(cluster, Double.MAX_VALUE);
BalanceAction action = loadBalancer.nextAction(cluster);
cluster.doAction(action);
loadBalancer.updateCostsWithAction(cluster, action);
BalanceAction undoAction = action.undoAction();
cluster.doAction(undoAction);
loadBalancer.updateCostsWithAction(cluster, undoAction);
final double actualCost = loadBalancer.computeCost(cluster, Double.MAX_VALUE);
assertEquals(expectedCost, actualCost, 0);
}
}
}
@Test
public void testTableSkewCost() {
Configuration conf = HBaseConfiguration.create();
CostFunction
costFunction = new TableSkewCostFunction(conf);
for (int[] mockCluster : clusterStateMocks) {
BalancerClusterState cluster = mockCluster(mockCluster);
costFunction.init(cluster);
double cost = costFunction.cost();
assertTrue(cost >= 0);
assertTrue(cost <= 1.01);
}
}
@Test
public void testRegionLoadCost() {
List<BalancerRegionLoad> regionLoads = new ArrayList<>();
for (int i = 1; i < 5; i++) {
BalancerRegionLoad regionLoad = mock(BalancerRegionLoad.class);
when(regionLoad.getReadRequestsCount()).thenReturn(new Long(i));
when(regionLoad.getCpRequestsCount()).thenReturn(new Long(i));
when(regionLoad.getStorefileSizeMB()).thenReturn(i);
regionLoads.add(regionLoad);
}
Configuration conf = HBaseConfiguration.create();
ReadRequestCostFunction readCostFunction =
new ReadRequestCostFunction(conf);
double rateResult = readCostFunction.getRegionLoadCost(regionLoads);
// read requests are treated as a rate so the average rate here is simply 1
assertEquals(1, rateResult, 0.01);
CPRequestCostFunction cpCostFunction =
new CPRequestCostFunction(conf);
rateResult = cpCostFunction.getRegionLoadCost(regionLoads);
// coprocessor requests are treated as a rate so the average rate here is simply 1
assertEquals(1, rateResult, 0.01);
StoreFileCostFunction storeFileCostFunction =
new StoreFileCostFunction(conf);
double result = storeFileCostFunction.getRegionLoadCost(regionLoads);
// storefile size cost is simply an average of it's value over time
assertEquals(2.5, result, 0.01);
}
@Test
public void testCostFromArray() {
Configuration conf = HBaseConfiguration.create();
CostFromRegionLoadFunction costFunction = new MemStoreSizeCostFunction(conf);
costFunction.init(mockCluster(new int[] { 0, 0, 0, 0, 1 }));
double[] statOne = new double[100];
for (int i = 0; i < 100; i++) {
statOne[i] = 10;
}
assertEquals(0, costFunction.costFromArray(statOne), 0.01);
double[] statTwo = new double[101];
for (int i = 0; i < 100; i++) {
statTwo[i] = 0;
}
statTwo[100] = 100;
assertEquals(1, costFunction.costFromArray(statTwo), 0.01);
double[] statThree = new double[200];
for (int i = 0; i < 100; i++) {
statThree[i] = 0;
statThree[i + 100] = 100;
}
assertEquals(0.5, costFunction.costFromArray(statThree), 0.01);
}
@Test
public void testLosingRs() throws Exception {
int numNodes = 3;
int numRegions = 20;
int numRegionsPerServer = 3; //all servers except one
int replication = 1;
int numTables = 2;
Map<ServerName, List<RegionInfo>> serverMap =
createServerMap(numNodes, numRegions, numRegionsPerServer, replication, numTables);
List<ServerAndLoad> list = convertToList(serverMap);
List<RegionPlan> plans = loadBalancer.balanceTable(HConstants.ENSEMBLE_TABLE_NAME, serverMap);
assertNotNull(plans);
// Apply the plan to the mock cluster.
List<ServerAndLoad> balancedCluster = reconcile(list, plans, serverMap);
assertClusterAsBalanced(balancedCluster);
ServerName sn = serverMap.keySet().toArray(new ServerName[serverMap.size()])[0];
ServerName deadSn = ServerName.valueOf(sn.getHostname(), sn.getPort(), sn.getStartcode() - 100);
serverMap.put(deadSn, new ArrayList<>(0));
plans = loadBalancer.balanceTable(HConstants.ENSEMBLE_TABLE_NAME, serverMap);
assertNull(plans);
}
@Test
public void testAdditionalCostFunction() {
try {
conf.set(StochasticLoadBalancer.COST_FUNCTIONS_COST_FUNCTIONS_KEY,
DummyCostFunction.class.getName());
loadBalancer.setConf(conf);
assertTrue(Arrays.
asList(loadBalancer.getCostFunctionNames()).
contains(DummyCostFunction.class.getSimpleName()));
} finally {
conf.unset(StochasticLoadBalancer.COST_FUNCTIONS_COST_FUNCTIONS_KEY);
loadBalancer.setConf(conf);
}
}
@Test
public void testDefaultCostFunctionList() {
List<String> expected = Arrays.asList(
RegionCountSkewCostFunction.class.getSimpleName(),
PrimaryRegionCountSkewCostFunction.class.getSimpleName(),
MoveCostFunction.class.getSimpleName(),
RackLocalityCostFunction.class.getSimpleName(),
TableSkewCostFunction.class.getSimpleName(),
RegionReplicaHostCostFunction.class.getSimpleName(),
RegionReplicaRackCostFunction.class.getSimpleName(),
ReadRequestCostFunction.class.getSimpleName(),
CPRequestCostFunction.class.getSimpleName(),
WriteRequestCostFunction.class.getSimpleName(),
MemStoreSizeCostFunction.class.getSimpleName(),
StoreFileCostFunction.class.getSimpleName()
);
List<String> actual = Arrays.asList(loadBalancer.getCostFunctionNames());
assertTrue("ExpectedCostFunctions: " + expected + " ActualCostFunctions: " + actual,
CollectionUtils.isEqualCollection(expected, actual));
}
private boolean needsBalanceIdleRegion(int[] cluster) {
return Arrays.stream(cluster).anyMatch(x -> x > 1) &&
Arrays.stream(cluster).anyMatch(x -> x < 1);
}
// This mock allows us to test the LocalityCostFunction
private class MockCluster extends BalancerClusterState {
private int[][] localities = null; // [region][server] = percent of blocks
public MockCluster(int[][] regions) {
// regions[0] is an array where index = serverIndex an value = number of regions
super(mockClusterServers(regions[0], 1), null, null, null);
localities = new int[regions.length - 1][];
for (int i = 1; i < regions.length; i++) {
int regionIndex = i - 1;
localities[regionIndex] = new int[regions[i].length - 1];
regionIndexToServerIndex[regionIndex] = regions[i][0];
for (int j = 1; j < regions[i].length; j++) {
int serverIndex = j - 1;
localities[regionIndex][serverIndex] =
regions[i][j] > 100 ? regions[i][j] % 100 : regions[i][j];
}
}
}
@Override
float getLocalityOfRegion(int region, int server) {
// convert the locality percentage to a fraction
return localities[region][server] / 100.0f;
}
@Override
public int getRegionSizeMB(int region) {
return 1;
}
}
}