Initial Changes

hbase-balancer/src/main/java/org/apache/hadoop/hbase/master/balancer/MutuallyExclusiveTablesCostFunction.java

@@ -0,0 +1,80 @@
+/*
+ * 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.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.ServerName;
+import org.apache.hadoop.hbase.client.RegionInfo;
+import org.apache.yetus.audience.InterfaceAudience;
+
+import java.util.*;
+
+/**
+ * Ensure Tables are mutually exclusive on an RS
+ * for example: META and SYSTEM.CATALOG can be mutually exclusive Tables
+ * on same RS
+ */
+@InterfaceAudience.Private public class MutuallyExclusiveTablesCostFunction extends CostFunction {
+ private static final String MUTUALLY_EXCLUSIVE_TABLES_KEY =
+ "hbase.master.balancer.stochastic.mutuallyExclusiveTables";
+ private static final String MUTUALLY_EXCLUSIVE_TABLES_COST_KEY =
+ "hbase.master.balancer.stochastic.mutuallyExclusiveTablesCost";
+ private static final float DEFAULT_MUTUALLY_EXCLUSIVE_TABLES_COST = 10000;
+ private Set<String> mutuallyExclusiveTables = Collections.emptySet();
+
+ public MutuallyExclusiveTablesCostFunction(Configuration conf) {
+ this.setMultiplier(
+ conf.getFloat(MUTUALLY_EXCLUSIVE_TABLES_COST_KEY, DEFAULT_MUTUALLY_EXCLUSIVE_TABLES_COST));
+ initializeMutuallyExclusiveTables(conf);
+ }
+
+ private void initializeMutuallyExclusiveTables(Configuration conf) {
+ String[] tables = conf.getStrings(MUTUALLY_EXCLUSIVE_TABLES_KEY);
+ if (tables != null && tables.length > 0) {
+ this.mutuallyExclusiveTables = new HashSet<>(Arrays.asList(tables));
+ }
+ }
+
+ @Override void prepare(BalancerClusterState cluster) {
+ super.prepare(cluster);
+ }
+
+ @Override protected double cost() {
+ double totalCost = 0;
+
+ Map<ServerName, List<RegionInfo>> clusterState = this.cluster.clusterState;
+
+ for (Map.Entry<ServerName, List<RegionInfo>> entry : clusterState.entrySet()) {
+ List<RegionInfo> regions = entry.getValue();
+
+ Set<String> tablesOnServer = new HashSet<>();
+ for (RegionInfo regionInfo : regions) {
+ String tableName = regionInfo.getTable().getNameAsString();
+ if (mutuallyExclusiveTables.contains(tableName)) {
+ if (tablesOnServer.contains(tableName)) {
+ totalCost += 10000; // Arbitrarily high cost to penalize this configuration
+ } else {
+ tablesOnServer.add(tableName);
+ }
+ }
+ }
+ }
+
+ return totalCost;
+ }
+}