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Posted to commits@hbase.apache.org by zh...@apache.org on 2021/04/23 08:33:39 UTC
[hbase] branch branch-2 updated: HBASE-25802 Miscellaneous style
improvements for load balancer related classes (#3192)
This is an automated email from the ASF dual-hosted git repository.
zhangduo pushed a commit to branch branch-2
in repository https://gitbox.apache.org/repos/asf/hbase.git
The following commit(s) were added to refs/heads/branch-2 by this push:
new f374357 HBASE-25802 Miscellaneous style improvements for load balancer related classes (#3192)
f374357 is described below
commit f374357cc31b1e9be7ddc8b608a756382bb92806
Author: Duo Zhang <zh...@apache.org>
AuthorDate: Fri Apr 23 15:20:27 2021 +0800
HBASE-25802 Miscellaneous style improvements for load balancer related classes (#3192)
Signed-off-by: Yulin Niu <ni...@apache.org>
---
.../hbase/master/balancer/BaseLoadBalancer.java | 65 +++++-----
.../hbase/master/balancer/CandidateGenerator.java | 9 +-
.../master/balancer/FavoredStochasticBalancer.java | 9 +-
.../master/balancer/RandomCandidateGenerator.java | 34 ++++++
.../balancer/RegionReplicaCandidateGenerator.java | 6 +-
.../RegionReplicaRackCandidateGenerator.java | 54 +++++++++
.../hbase/master/balancer/SimpleLoadBalancer.java | 133 +++++++++++++--------
.../master/balancer/StochasticLoadBalancer.java | 59 +--------
.../master/balancer/TestBaseLoadBalancer.java | 39 ++----
...estStochasticLoadBalancerHeterogeneousCost.java | 2 +-
10 files changed, 233 insertions(+), 177 deletions(-)
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.java
index 9840a0e..f5c462f 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.java
@@ -35,7 +35,6 @@ import java.util.function.Predicate;
import java.util.stream.Collectors;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.ClusterMetrics;
-import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HBaseIOException;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.ServerMetrics;
@@ -66,6 +65,8 @@ import org.apache.hbase.thirdparty.com.google.common.collect.Sets;
@InterfaceAudience.Private
public abstract class BaseLoadBalancer implements LoadBalancer {
+ private static final Logger LOG = LoggerFactory.getLogger(BaseLoadBalancer.class);
+
public static final String BALANCER_DECISION_BUFFER_ENABLED =
"hbase.master.balancer.decision.buffer.enabled";
public static final boolean DEFAULT_BALANCER_DECISION_BUFFER_ENABLED = false;
@@ -73,46 +74,19 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
protected static final int MIN_SERVER_BALANCE = 2;
private volatile boolean stopped = false;
- static final List<RegionInfo> EMPTY_REGION_LIST = Collections.emptyList();
-
- static final Predicate<ServerMetrics> IDLE_SERVER_PREDICATOR
+ private static final Predicate<ServerMetrics> IDLE_SERVER_PREDICATOR
= load -> load.getRegionMetrics().isEmpty();
protected RegionLocationFinder regionFinder;
protected boolean useRegionFinder;
protected boolean isByTable = false;
- /**
- * The constructor that uses the basic MetricsBalancer
- */
- protected BaseLoadBalancer() {
- metricsBalancer = new MetricsBalancer();
- createRegionFinder();
- }
-
- /**
- * This Constructor accepts an instance of MetricsBalancer,
- * which will be used instead of creating a new one
- */
- protected BaseLoadBalancer(MetricsBalancer metricsBalancer) {
- this.metricsBalancer = (metricsBalancer != null) ? metricsBalancer : new MetricsBalancer();
- createRegionFinder();
- }
-
- private void createRegionFinder() {
- useRegionFinder = config.getBoolean("hbase.master.balancer.uselocality", true);
- if (useRegionFinder) {
- regionFinder = new RegionLocationFinder();
- }
- }
-
// slop for regions
protected float slop;
// overallSlop to control simpleLoadBalancer's cluster level threshold
protected float overallSlop;
- protected Configuration config = HBaseConfiguration.create();
+ protected Configuration config;
protected RackManager rackManager;
- static final Logger LOG = LoggerFactory.getLogger(BaseLoadBalancer.class);
protected MetricsBalancer metricsBalancer = null;
protected ClusterMetrics clusterStatus = null;
protected ServerName masterServerName;
@@ -125,6 +99,21 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
@Deprecated
protected boolean onlySystemTablesOnMaster;
+ /**
+ * The constructor that uses the basic MetricsBalancer
+ */
+ protected BaseLoadBalancer() {
+ this(null);
+ }
+
+ /**
+ * This Constructor accepts an instance of MetricsBalancer,
+ * which will be used instead of creating a new one
+ */
+ protected BaseLoadBalancer(MetricsBalancer metricsBalancer) {
+ this.metricsBalancer = (metricsBalancer != null) ? metricsBalancer : new MetricsBalancer();
+ }
+
@Override
public void setConf(Configuration conf) {
this.config = conf;
@@ -144,7 +133,9 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
this.onlySystemTablesOnMaster = LoadBalancer.isSystemTablesOnlyOnMaster(this.config);
this.rackManager = new RackManager(getConf());
+ useRegionFinder = config.getBoolean("hbase.master.balancer.uselocality", true);
if (useRegionFinder) {
+ regionFinder = new RegionLocationFinder();
regionFinder.setConf(conf);
}
this.isByTable = conf.getBoolean(HConstants.HBASE_MASTER_LOADBALANCE_BYTABLE, isByTable);
@@ -295,7 +286,9 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
}
return false;
}
- if(areSomeRegionReplicasColocated(c)) return true;
+ if (areSomeRegionReplicasColocated(c)) {
+ return true;
+ }
if(idleRegionServerExist(c)) {
return true;
}
@@ -348,10 +341,10 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
/**
* Generates a bulk assignment plan to be used on cluster startup using a
* simple round-robin assignment.
- * <p>
+ * <p/>
* Takes a list of all the regions and all the servers in the cluster and
* returns a map of each server to the regions that it should be assigned.
- * <p>
+ * <p/>
* Currently implemented as a round-robin assignment. Same invariant as load
* balancing, all servers holding floor(avg) or ceiling(avg).
*
@@ -407,7 +400,7 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
return assignments;
}
- protected BalancerClusterState createCluster(List<ServerName> servers,
+ private BalancerClusterState createCluster(List<ServerName> servers,
Collection<RegionInfo> regions) throws HBaseIOException {
boolean hasRegionReplica = false;
try {
@@ -439,7 +432,7 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
for (ServerName server : servers) {
if (!clusterState.containsKey(server)) {
- clusterState.put(server, EMPTY_REGION_LIST);
+ clusterState.put(server, Collections.emptyList());
}
}
return new BalancerClusterState(regions, clusterState, null, this.regionFinder,
@@ -758,7 +751,7 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
}
}
- protected Map<ServerName, List<RegionInfo>> getRegionAssignmentsByServer(
+ private Map<ServerName, List<RegionInfo>> getRegionAssignmentsByServer(
Collection<RegionInfo> regions) {
if (this.services != null && this.services.getAssignmentManager() != null) {
return this.services.getAssignmentManager().getSnapShotOfAssignment(regions);
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CandidateGenerator.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CandidateGenerator.java
index 06b5623..cf43269 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CandidateGenerator.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CandidateGenerator.java
@@ -19,6 +19,7 @@
package org.apache.hadoop.hbase.master.balancer;
import java.util.Map;
+import java.util.concurrent.ThreadLocalRandom;
import org.apache.hadoop.hbase.client.RegionInfo;
import org.apache.yetus.audience.InterfaceAudience;
@@ -46,11 +47,11 @@ abstract class CandidateGenerator {
double chanceOfNoSwap) {
// Check to see if this is just a move.
if (cluster.regionsPerServer[server].length == 0
- || StochasticLoadBalancer.RANDOM.nextFloat() < chanceOfNoSwap) {
+ || ThreadLocalRandom.current().nextFloat() < chanceOfNoSwap) {
// signal a move only.
return -1;
}
- int rand = StochasticLoadBalancer.RANDOM.nextInt(cluster.regionsPerServer[server].length);
+ int rand = ThreadLocalRandom.current().nextInt(cluster.regionsPerServer[server].length);
return cluster.regionsPerServer[server][rand];
}
@@ -59,7 +60,7 @@ abstract class CandidateGenerator {
return -1;
}
- return StochasticLoadBalancer.RANDOM.nextInt(cluster.numServers);
+ return ThreadLocalRandom.current().nextInt(cluster.numServers);
}
int pickRandomRack(BalancerClusterState cluster) {
@@ -67,7 +68,7 @@ abstract class CandidateGenerator {
return -1;
}
- return StochasticLoadBalancer.RANDOM.nextInt(cluster.numRacks);
+ return ThreadLocalRandom.current().nextInt(cluster.numRacks);
}
int pickOtherRandomServer(BalancerClusterState cluster, int serverIndex) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.java
index 8bf0fa5..df047dc 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.java
@@ -32,7 +32,7 @@ import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
-
+import java.util.concurrent.ThreadLocalRandom;
import org.apache.hadoop.hbase.HBaseIOException;
import org.apache.hadoop.hbase.ServerMetrics;
import org.apache.hadoop.hbase.ServerName;
@@ -290,7 +290,7 @@ public class FavoredStochasticBalancer extends StochasticLoadBalancer implements
}
} else {
// We don't have one/more load, lets just choose a random node
- s = RANDOM.nextBoolean() ? secondaryHost : tertiaryHost;
+ s = ThreadLocalRandom.current().nextBoolean() ? secondaryHost : tertiaryHost;
}
addRegionToMap(assignmentMapForFavoredNodes, region, s);
} else if (secondaryHost != null) {
@@ -348,7 +348,7 @@ public class FavoredStochasticBalancer extends StochasticLoadBalancer implements
List<ServerName> onlineServers = getOnlineFavoredNodes(servers, favoredNodes);
if (onlineServers.size() > 0) {
- destination = onlineServers.get(RANDOM.nextInt(onlineServers.size()));
+ destination = onlineServers.get(ThreadLocalRandom.current().nextInt(onlineServers.size()));
}
boolean alwaysAssign = getConf().getBoolean(FAVORED_ALWAYS_ASSIGN_REGIONS, true);
@@ -433,7 +433,8 @@ public class FavoredStochasticBalancer extends StochasticLoadBalancer implements
if (FavoredNodesPlan.getFavoredServerPosition(favoredNodes, sn) != null) {
addRegionToMap(assignmentMap, hri, sn);
} else {
- ServerName destination = onlineFN.get(RANDOM.nextInt(onlineFN.size()));
+ ServerName destination =
+ onlineFN.get(ThreadLocalRandom.current().nextInt(onlineFN.size()));
LOG.warn("Region: " + hri + " not hosted on favored nodes: " + favoredNodes
+ " current: " + sn + " moving to: " + destination);
addRegionToMap(assignmentMap, hri, destination);
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RandomCandidateGenerator.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RandomCandidateGenerator.java
new file mode 100644
index 0000000..c2cd998
--- /dev/null
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RandomCandidateGenerator.java
@@ -0,0 +1,34 @@
+/*
+ * 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 org.apache.yetus.audience.InterfaceAudience;
+
+@InterfaceAudience.Private
+class RandomCandidateGenerator extends CandidateGenerator {
+
+ @Override
+ BalanceAction generate(BalancerClusterState cluster) {
+ int thisServer = pickRandomServer(cluster);
+
+ // Pick the other server
+ int otherServer = pickOtherRandomServer(cluster, thisServer);
+
+ return pickRandomRegions(cluster, thisServer, otherServer);
+ }
+}
\ No newline at end of file
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionReplicaCandidateGenerator.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionReplicaCandidateGenerator.java
index 4badd4d..f3b6955 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionReplicaCandidateGenerator.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionReplicaCandidateGenerator.java
@@ -18,6 +18,7 @@
package org.apache.hadoop.hbase.master.balancer;
+import java.util.concurrent.ThreadLocalRandom;
import org.apache.yetus.audience.InterfaceAudience;
/**
@@ -27,8 +28,7 @@ import org.apache.yetus.audience.InterfaceAudience;
@InterfaceAudience.Private
class RegionReplicaCandidateGenerator extends CandidateGenerator {
- StochasticLoadBalancer.RandomCandidateGenerator randomGenerator =
- new StochasticLoadBalancer.RandomCandidateGenerator();
+ protected final RandomCandidateGenerator randomGenerator = new RandomCandidateGenerator();
/**
* Randomly select one regionIndex out of all region replicas co-hosted in the same group
@@ -56,7 +56,7 @@ class RegionReplicaCandidateGenerator extends CandidateGenerator {
int numReplicas = j - currentPrimaryIndex;
if (numReplicas > 1) { // means consecutive primaries, indicating co-location
// decide to select this primary region id or not
- double currentRandom = StochasticLoadBalancer.RANDOM.nextDouble();
+ double currentRandom = ThreadLocalRandom.current().nextDouble();
// we don't know how many region replicas are co-hosted, we will randomly select one
// using reservoir sampling (http://gregable.com/2007/10/reservoir-sampling.html)
if (currentRandom > currentLargestRandom) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionReplicaRackCandidateGenerator.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionReplicaRackCandidateGenerator.java
new file mode 100644
index 0000000..a67dc1d
--- /dev/null
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionReplicaRackCandidateGenerator.java
@@ -0,0 +1,54 @@
+/*
+ * 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.concurrent.ThreadLocalRandom;
+import org.apache.yetus.audience.InterfaceAudience;
+
+/**
+ * Generates candidates which moves the replicas out of the rack for co-hosted region replicas in
+ * the same rack
+ */
+@InterfaceAudience.Private
+class RegionReplicaRackCandidateGenerator extends RegionReplicaCandidateGenerator {
+
+ @Override
+ BalanceAction generate(BalancerClusterState cluster) {
+ int rackIndex = pickRandomRack(cluster);
+ if (cluster.numRacks <= 1 || rackIndex == -1) {
+ return super.generate(cluster);
+ }
+
+ int regionIndex = selectCoHostedRegionPerGroup(cluster.primariesOfRegionsPerRack[rackIndex],
+ cluster.regionsPerRack[rackIndex], cluster.regionIndexToPrimaryIndex);
+
+ // if there are no pairs of region replicas co-hosted, default to random generator
+ if (regionIndex == -1) {
+ // default to randompicker
+ return randomGenerator.generate(cluster);
+ }
+
+ int serverIndex = cluster.regionIndexToServerIndex[regionIndex];
+ int toRackIndex = pickOtherRandomRack(cluster, rackIndex);
+
+ int rand = ThreadLocalRandom.current().nextInt(cluster.serversPerRack[toRackIndex].length);
+ int toServerIndex = cluster.serversPerRack[toRackIndex][rand];
+ int toRegionIndex = pickRandomRegion(cluster, toServerIndex, 0.9f);
+ return getAction(serverIndex, regionIndex, toServerIndex, toRegionIndex);
+ }
+}
\ No newline at end of file
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/SimpleLoadBalancer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/SimpleLoadBalancer.java
index a0b6139..f255854 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/SimpleLoadBalancer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/SimpleLoadBalancer.java
@@ -25,7 +25,6 @@ import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.NavigableMap;
-import java.util.Random;
import java.util.TreeMap;
import org.apache.hadoop.conf.Configuration;
@@ -41,22 +40,20 @@ import org.slf4j.LoggerFactory;
import org.apache.hbase.thirdparty.com.google.common.collect.MinMaxPriorityQueue;
/**
- * Makes decisions about the placement and movement of Regions across
- * RegionServers.
- *
- * <p>Cluster-wide load balancing will occur only when there are no regions in
- * transition and according to a fixed period of a time using {@link #balanceCluster(Map)}.
- *
- * <p>On cluster startup, bulk assignment can be used to determine
- * locations for all Regions in a cluster.
- *
- * <p>This classes produces plans for the
+ * Makes decisions about the placement and movement of Regions across RegionServers.
+ * <p/>
+ * Cluster-wide load balancing will occur only when there are no regions in transition and according
+ * to a fixed period of a time using {@link #balanceCluster(Map)}.
+ * <p/>
+ * On cluster startup, bulk assignment can be used to determine locations for all Regions in a
+ * cluster.
+ * <p/>
+ * This classes produces plans for the
* {@link org.apache.hadoop.hbase.master.assignment.AssignmentManager} to execute.
*/
@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
public class SimpleLoadBalancer extends BaseLoadBalancer {
private static final Logger LOG = LoggerFactory.getLogger(SimpleLoadBalancer.class);
- private static final Random RANDOM = new Random(System.currentTimeMillis());
private RegionInfoComparator riComparator = new RegionInfoComparator();
private RegionPlan.RegionPlanComparator rpComparator = new RegionPlan.RegionPlanComparator();
@@ -66,12 +63,12 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
/**
* Stores additional per-server information about the regions added/removed
* during the run of the balancing algorithm.
- *
+ * </p>
* For servers that shed regions, we need to track which regions we have already
* shed. <b>nextRegionForUnload</b> contains the index in the list of regions on
* the server that is the next to be shed.
*/
- static class BalanceInfo {
+ private static final class BalanceInfo {
private int nextRegionForUnload;
private int numRegionsAdded;
@@ -139,8 +136,9 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
originSlop, slop, originOverallSlop, overallSlop);
}
- private void setLoad(List<ServerAndLoad> slList, int i, int loadChange){
- ServerAndLoad newsl = new ServerAndLoad(slList.get(i).getServerName(),slList.get(i).getLoad() + loadChange);
+ private void setLoad(List<ServerAndLoad> slList, int i, int loadChange) {
+ ServerAndLoad newsl =
+ new ServerAndLoad(slList.get(i).getServerName(), slList.get(i).getLoad() + loadChange);
slList.set(i, newsl);
}
@@ -328,7 +326,9 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
&& masterServerName.equals(sal.getServerName())) continue;
regionsToMove.add(new RegionPlan(hri, sal.getServerName(), null));
numTaken++;
- if (numTaken >= numToOffload) break;
+ if (numTaken >= numToOffload) {
+ break;
+ }
}
serverBalanceInfo.put(sal.getServerName(),
new BalanceInfo(numToOffload, (-1)*numTaken, server.getValue()));
@@ -343,7 +343,9 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
int maxToTake = numRegions - min;
for (Map.Entry<ServerAndLoad, List<RegionInfo>> server:
serversByLoad.entrySet()) {
- if (maxToTake == 0) break; // no more to take
+ if (maxToTake == 0) {
+ break; // no more to take
+ }
int load = server.getKey().getLoad();
if (load >= min) {
continue; // look for other servers which haven't reached min
@@ -357,15 +359,19 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
int incr = 1;
List<ServerName> sns =
Arrays.asList(underloadedServers.keySet().toArray(new ServerName[serversUnderloaded]));
- Collections.shuffle(sns, RANDOM);
+ Collections.shuffle(sns);
while (regionsToMove.size() > 0) {
int cnt = 0;
int i = incr > 0 ? 0 : underloadedServers.size()-1;
for (; i >= 0 && i < underloadedServers.size(); i += incr) {
- if (regionsToMove.isEmpty()) break;
+ if (regionsToMove.isEmpty()) {
+ break;
+ }
ServerName si = sns.get(i);
int numToTake = underloadedServers.get(si);
- if (numToTake == 0) continue;
+ if (numToTake == 0) {
+ continue;
+ }
addRegionPlan(regionsToMove, fetchFromTail, si, regionsToReturn);
@@ -374,7 +380,9 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
BalanceInfo bi = serverBalanceInfo.get(si);
bi.setNumRegionsAdded(bi.getNumRegionsAdded()+1);
}
- if (cnt == 0) break;
+ if (cnt == 0) {
+ break;
+ }
// iterates underloadedServers in the other direction
incr = -incr;
}
@@ -395,9 +403,13 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
serverBalanceInfo.get(server.getKey().getServerName());
int idx =
balanceInfo == null ? 0 : balanceInfo.getNextRegionForUnload();
- if (idx >= server.getValue().size()) break;
+ if (idx >= server.getValue().size()) {
+ break;
+ }
RegionInfo region = server.getValue().get(idx);
- if (region.isMetaRegion()) continue; // Don't move meta regions.
+ if (region.isMetaRegion()) {
+ continue; // Don't move meta regions.
+ }
regionsToMove.add(new RegionPlan(region, server.getKey().getServerName(), null));
balanceInfo.setNumRegionsAdded(balanceInfo.getNumRegionsAdded() - 1);
balanceInfo.setNextRegionForUnload(balanceInfo.getNextRegionForUnload() + 1);
@@ -416,7 +428,9 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
for (Map.Entry<ServerAndLoad, List<RegionInfo>> server :
serversByLoad.entrySet()) {
int regionCount = server.getKey().getLoad();
- if (regionCount >= min) break;
+ if (regionCount >= min) {
+ break;
+ }
BalanceInfo balanceInfo = serverBalanceInfo.get(server.getKey().getServerName());
if(balanceInfo != null) {
regionCount += balanceInfo.getNumRegionsAdded();
@@ -447,7 +461,9 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
", serversUnderloaded=" + serversUnderloaded);
StringBuilder sb = new StringBuilder();
for (Map.Entry<ServerName, List<RegionInfo>> e: loadOfOneTable.entrySet()) {
- if (sb.length() > 0) sb.append(", ");
+ if (sb.length() > 0) {
+ sb.append(", ");
+ }
sb.append(e.getKey().toString());
sb.append(" ");
sb.append(e.getValue().size());
@@ -465,15 +481,16 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
}
/**
- * If we need to balanceoverall, we need to add one more round to peel off one region from each max.
- * Together with other regions left to be assigned, we distribute all regionToMove, to the RS
+ * If we need to balanceoverall, we need to add one more round to peel off one region from each
+ * max. Together with other regions left to be assigned, we distribute all regionToMove, to the RS
* that have less regions in whole cluster scope.
*/
public void balanceOverall(List<RegionPlan> regionsToReturn,
- Map<ServerName, BalanceInfo> serverBalanceInfo, boolean fetchFromTail,
- MinMaxPriorityQueue<RegionPlan> regionsToMove, int max, int min ){
+ Map<ServerName, BalanceInfo> serverBalanceInfo, boolean fetchFromTail,
+ MinMaxPriorityQueue<RegionPlan> regionsToMove, int max, int min) {
// Step 1.
- // A map to record the plan we have already got as status quo, in order to resolve a cyclic assignment pair,
+ // A map to record the plan we have already got as status quo, in order to resolve a cyclic
+ // assignment pair,
// e.g. plan 1: A -> B, plan 2: B ->C => resolve plan1 to A -> C, remove plan2
Map<ServerName, List<Integer>> returnMap = new HashMap<>();
for (int i = 0; i < regionsToReturn.size(); i++) {
@@ -509,12 +526,14 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
RegionPlan maxPlan = new RegionPlan(hriToPlan, serverload.getServerName(), null);
regionsToMove.add(maxPlan);
setLoad(serverLoadList, i, -1);
- }else if(balanceInfo.getHriList().size() + balanceInfo.getNumRegionsAdded() > max
- || balanceInfo.getHriList().size() + balanceInfo.getNumRegionsAdded() < min){
- LOG.warn("Encounter incorrect region numbers after calculating move plan during balanceOverall, " +
- "for this table, " + serverload.getServerName() + " originally has " + balanceInfo.getHriList().size() +
- " regions and " + balanceInfo.getNumRegionsAdded() + " regions have been added. Yet, max =" +
- max + ", min =" + min + ". Thus stop balance for this table"); // should not happen
+ } else if (balanceInfo.getHriList().size() + balanceInfo.getNumRegionsAdded() > max ||
+ balanceInfo.getHriList().size() + balanceInfo.getNumRegionsAdded() < min) {
+ LOG.warn(
+ "Encounter incorrect region numbers after calculating move plan during balanceOverall, " +
+ "for this table, " + serverload.getServerName() + " originally has " +
+ balanceInfo.getHriList().size() + " regions and " + balanceInfo.getNumRegionsAdded() +
+ " regions have been added. Yet, max =" + max + ", min =" + min +
+ ". Thus stop balance for this table"); // should not happen
return;
}
}
@@ -522,12 +541,16 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
// Step 3. sort the ServerLoadList, the ArrayList hold overall load for each server.
// We only need to assign the regionsToMove to
// the first n = regionsToMove.size() RS that has least load.
- Collections.sort(serverLoadList,new Comparator<ServerAndLoad>(){
+ Collections.sort(serverLoadList, new Comparator<ServerAndLoad>() {
@Override
public int compare(ServerAndLoad s1, ServerAndLoad s2) {
- if(s1.getLoad() == s2.getLoad()) return 0;
- else return (s1.getLoad() > s2.getLoad())? 1 : -1;
- }});
+ if (s1.getLoad() == s2.getLoad()) {
+ return 0;
+ } else {
+ return (s1.getLoad() > s2.getLoad()) ? 1 : -1;
+ }
+ }
+ });
// Step 4.
// Preparation before assign out all regionsToMove.
@@ -542,16 +565,19 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
Pair<ServerAndLoad,Integer> shredLoad;
// A List to help mark the plan in regionsToMove that should be removed
List<RegionPlan> planToRemoveList = new ArrayList<>();
- // A structure to record how many times a server becomes the source of a plan, from regionsToMove.
+ // A structure to record how many times a server becomes the source of a plan, from
+ // regionsToMove.
Map<ServerName, Integer> sourceMap = new HashMap<>();
// We remove one of the plan which would cause source RS equals destination RS.
// But we should keep in mind that the second plan from such RS should be kept.
for(RegionPlan plan: regionsToMove){
// the source RS's load and index in ServerLoadList
shredLoad = SnLoadMap.get(plan.getSource());
- if(!sourceMap.containsKey(plan.getSource())) sourceMap.put(plan.getSource(), 0);
+ if (!sourceMap.containsKey(plan.getSource())) {
+ sourceMap.put(plan.getSource(), 0);
+ }
sourceMap.put(plan.getSource(), sourceMap.get(plan.getSource()) + 1);
- if(shredLoad.getSecond() < assignLength && sourceMap.get(plan.getSource()) == 1) {
+ if (shredLoad.getSecond() < assignLength && sourceMap.get(plan.getSource()) == 1) {
planToRemoveList.add(plan);
// While marked as to be removed, the count should be add back to the source RS
setLoad(serverLoadList, shredLoad.getSecond(), 1);
@@ -570,14 +596,18 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
// With this strategy adopted, we can gradually achieve the overall balance,
// while keeping table level balanced.
for(int i = 0; i < assignLength; i++){
- // skip the RS that is also the source, we have removed them from regionsToMove in previous step
- if(sourceMap.containsKey(serverLoadList.get(i).getServerName())) continue;
+ // skip the RS that is also the source, we have removed them from regionsToMove in previous
+ // step
+ if (sourceMap.containsKey(serverLoadList.get(i).getServerName())) {
+ continue;
+ }
addRegionPlan(regionsToMove, fetchFromTail,
serverLoadList.get(i).getServerName(), regionsToReturn);
setLoad(serverLoadList, i, 1);
// resolve a possible cyclic assignment pair if we just produced one:
// e.g. plan1: A -> B, plan2: B -> C => resolve plan1 to A -> C and remove plan2
- List<Integer> pos = returnMap.get(regionsToReturn.get(regionsToReturn.size() - 1).getSource());
+ List<Integer> pos =
+ returnMap.get(regionsToReturn.get(regionsToReturn.size() - 1).getSource());
if (pos != null && pos.size() != 0) {
regionsToReturn.get(pos.get(pos.size() - 1)).setDestination(
regionsToReturn.get(regionsToReturn.size() - 1).getDestination());
@@ -592,10 +622,13 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
* Add a region from the head or tail to the List of regions to return.
*/
private void addRegionPlan(final MinMaxPriorityQueue<RegionPlan> regionsToMove,
- final boolean fetchFromTail, final ServerName sn, List<RegionPlan> regionsToReturn) {
+ final boolean fetchFromTail, final ServerName sn, List<RegionPlan> regionsToReturn) {
RegionPlan rp = null;
- if (!fetchFromTail) rp = regionsToMove.remove();
- else rp = regionsToMove.removeLast();
+ if (!fetchFromTail) {
+ rp = regionsToMove.remove();
+ } else {
+ rp = regionsToMove.removeLast();
+ }
rp.setDestination(sn);
regionsToReturn.add(rp);
}
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java
index 4859494..2dba908 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java
@@ -27,7 +27,7 @@ import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Objects;
-import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
import java.util.stream.Collectors;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.ClusterMetrics;
@@ -106,6 +106,8 @@ import org.apache.hbase.thirdparty.com.google.common.collect.Lists;
justification="Complaint is about costFunctions not being synchronized; not end of the world")
public class StochasticLoadBalancer extends BaseLoadBalancer {
+ private static final Logger LOG = LoggerFactory.getLogger(StochasticLoadBalancer.class);
+
protected static final String STEPS_PER_REGION_KEY =
"hbase.master.balancer.stochastic.stepsPerRegion";
protected static final String MAX_STEPS_KEY =
@@ -122,9 +124,6 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
protected static final String COST_FUNCTIONS_COST_FUNCTIONS_KEY =
"hbase.master.balancer.stochastic.additionalCostFunctions";
- protected static final Random RANDOM = new Random(System.currentTimeMillis());
- private static final Logger LOG = LoggerFactory.getLogger(StochasticLoadBalancer.class);
-
Map<String, Deque<BalancerRegionLoad>> loads = new HashMap<>();
// values are defaults
@@ -363,8 +362,8 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
}
BalanceAction nextAction(BalancerClusterState cluster) {
- return candidateGenerators.get(RANDOM.nextInt(candidateGenerators.size()))
- .generate(cluster);
+ return candidateGenerators.get(ThreadLocalRandom.current().nextInt(candidateGenerators.size()))
+ .generate(cluster);
}
/**
@@ -694,53 +693,6 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
return total;
}
- static class RandomCandidateGenerator extends CandidateGenerator {
-
- @Override
- BalanceAction generate(BalancerClusterState cluster) {
-
- int thisServer = pickRandomServer(cluster);
-
- // Pick the other server
- int otherServer = pickOtherRandomServer(cluster, thisServer);
-
- return pickRandomRegions(cluster, thisServer, otherServer);
- }
- }
-
- /**
- * Generates candidates which moves the replicas out of the rack for
- * co-hosted region replicas in the same rack
- */
- static class RegionReplicaRackCandidateGenerator extends RegionReplicaCandidateGenerator {
- @Override
- BalanceAction generate(BalancerClusterState cluster) {
- int rackIndex = pickRandomRack(cluster);
- if (cluster.numRacks <= 1 || rackIndex == -1) {
- return super.generate(cluster);
- }
-
- int regionIndex = selectCoHostedRegionPerGroup(
- cluster.primariesOfRegionsPerRack[rackIndex],
- cluster.regionsPerRack[rackIndex],
- cluster.regionIndexToPrimaryIndex);
-
- // if there are no pairs of region replicas co-hosted, default to random generator
- if (regionIndex == -1) {
- // default to randompicker
- return randomGenerator.generate(cluster);
- }
-
- int serverIndex = cluster.regionIndexToServerIndex[regionIndex];
- int toRackIndex = pickOtherRandomRack(cluster, rackIndex);
-
- int rand = RANDOM.nextInt(cluster.serversPerRack[toRackIndex].length);
- int toServerIndex = cluster.serversPerRack[toRackIndex][rand];
- int toRegionIndex = pickRandomRegion(cluster, toServerIndex, 0.9f);
- return getAction(serverIndex, regionIndex, toServerIndex, toRegionIndex);
- }
- }
-
/**
* Base class of StochasticLoadBalancer's Cost Functions.
*/
@@ -756,6 +708,7 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
boolean isNeeded() {
return true;
}
+
float getMultiplier() {
return multiplier;
}
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestBaseLoadBalancer.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestBaseLoadBalancer.java
index 288a121..54078a5 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestBaseLoadBalancer.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestBaseLoadBalancer.java
@@ -20,6 +20,8 @@ package org.apache.hadoop.hbase.master.balancer;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyList;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;
@@ -56,7 +58,6 @@ import org.junit.Rule;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.junit.rules.TestName;
-import org.mockito.Mockito;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@@ -92,22 +93,22 @@ public class TestBaseLoadBalancer extends BalancerTestBase {
conf.setClass("hbase.util.ip.to.rack.determiner", MockMapping.class, DNSToSwitchMapping.class);
loadBalancer = new MockBalancer();
loadBalancer.setConf(conf);
- MasterServices st = Mockito.mock(MasterServices.class);
- Mockito.when(st.getServerName()).thenReturn(master);
+ MasterServices st = mock(MasterServices.class);
+ when(st.getServerName()).thenReturn(master);
loadBalancer.setMasterServices(st);
// Set up the rack topologies (5 machines per rack)
- rackManager = Mockito.mock(RackManager.class);
+ rackManager = mock(RackManager.class);
for (int i = 0; i < NUM_SERVERS; i++) {
servers[i] = ServerName.valueOf("foo"+i+":1234",-1);
if (i < 5) {
- Mockito.when(rackManager.getRack(servers[i])).thenReturn("rack1");
+ when(rackManager.getRack(servers[i])).thenReturn("rack1");
}
if (i >= 5 && i < 10) {
- Mockito.when(rackManager.getRack(servers[i])).thenReturn("rack2");
+ when(rackManager.getRack(servers[i])).thenReturn("rack2");
}
if (i >= 10) {
- Mockito.when(rackManager.getRack(servers[i])).thenReturn("rack3");
+ when(rackManager.getRack(servers[i])).thenReturn("rack3");
}
}
}
@@ -127,19 +128,6 @@ public class TestBaseLoadBalancer extends BalancerTestBase {
}
/**
- * All regions have an assignment.
- * @param regions
- * @param servers
- * @param assignments
- */
- private void assertImmediateAssignment(List<RegionInfo> regions, List<ServerName> servers,
- Map<RegionInfo, ServerName> assignments) {
- for (RegionInfo region : regions) {
- assertTrue(assignments.containsKey(region));
- }
- }
-
- /**
* Tests the bulk assignment used during cluster startup.
*
* Round-robin. Should yield a balanced cluster so same invariant as the load
@@ -250,11 +238,10 @@ public class TestBaseLoadBalancer extends BalancerTestBase {
Configuration conf = HBaseConfiguration.create();
conf.setClass("hbase.util.ip.to.rack.determiner", MockMapping.class, DNSToSwitchMapping.class);
balancer.setConf(conf);
- ServerManager sm = Mockito.mock(ServerManager.class);
- Mockito.when(sm.getOnlineServersListWithPredicator(allServers, BaseLoadBalancer.IDLE_SERVER_PREDICATOR))
- .thenReturn(idleServers);
- MasterServices services = Mockito.mock(MasterServices.class);
- Mockito.when(services.getServerManager()).thenReturn(sm);
+ ServerManager sm = mock(ServerManager.class);
+ when(sm.getOnlineServersListWithPredicator(anyList(), any())).thenReturn(idleServers);
+ MasterServices services = mock(MasterServices.class);
+ when(services.getServerManager()).thenReturn(sm);
balancer.setMasterServices(services);
RegionInfo hri1 = RegionInfoBuilder.newBuilder(TableName.valueOf(name.getMethodName()))
.setStartKey("key1".getBytes())
@@ -262,7 +249,7 @@ public class TestBaseLoadBalancer extends BalancerTestBase {
.setSplit(false)
.setRegionId(100)
.build();
- assertNull(balancer.randomAssignment(hri1, Collections.EMPTY_LIST));
+ assertNull(balancer.randomAssignment(hri1, Collections.emptyList()));
assertNull(balancer.randomAssignment(hri1, null));
for (int i = 0; i != 3; ++i) {
ServerName sn = balancer.randomAssignment(hri1, allServers);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancerHeterogeneousCost.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancerHeterogeneousCost.java
index 8a2ec84..8ea7118 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancerHeterogeneousCost.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancerHeterogeneousCost.java
@@ -282,7 +282,7 @@ public class TestStochasticLoadBalancerHeterogeneousCost extends BalancerTestBas
}
static class FairRandomCandidateGenerator extends
- StochasticLoadBalancer.RandomCandidateGenerator {
+ RandomCandidateGenerator {
@Override
public BalanceAction pickRandomRegions(BalancerClusterState cluster,