001/**
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements.  See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership.  The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License.  You may obtain a copy of the License at
010 *
011 *     http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019
020package org.apache.hadoop.hbase.util;
021
022import java.io.IOException;
023import java.util.List;
024import java.util.concurrent.ExecutorService;
025import java.util.concurrent.LinkedBlockingQueue;
026import java.util.concurrent.ThreadLocalRandom;
027import java.util.concurrent.ThreadPoolExecutor;
028import java.util.concurrent.TimeUnit;
029
030import org.apache.hadoop.conf.Configuration;
031import org.apache.hadoop.hbase.HConstants;
032import org.apache.hadoop.hbase.TableName;
033import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
034import org.apache.yetus.audience.InterfaceAudience;
035import org.slf4j.Logger;
036import org.slf4j.LoggerFactory;
037import org.apache.hadoop.hbase.client.ClusterConnection;
038import org.apache.hadoop.hbase.client.Connection;
039import org.apache.hadoop.hbase.client.ConnectionFactory;
040import org.apache.hadoop.hbase.client.HTable;
041import org.apache.hadoop.hbase.client.Row;
042import org.apache.hadoop.hbase.client.coprocessor.Batch;
043
044/**
045 * Provides ability to create multiple Connection instances and allows to process a batch of
046 * actions using CHTable.doBatchWithCallback()
047 */
048@InterfaceAudience.Private
049public class MultiHConnection {
050  private static final Logger LOG = LoggerFactory.getLogger(MultiHConnection.class);
051  private Connection[] connections;
052  private final Object connectionsLock =  new Object();
053  private final int noOfConnections;
054  private ExecutorService batchPool;
055
056  /**
057   * Create multiple Connection instances and initialize a thread pool executor
058   * @param conf configuration
059   * @param noOfConnections total no of Connections to create
060   * @throws IOException if IO failure occurs
061   */
062  public MultiHConnection(Configuration conf, int noOfConnections)
063      throws IOException {
064    this.noOfConnections = noOfConnections;
065    synchronized (this.connectionsLock) {
066      connections = new Connection[noOfConnections];
067      for (int i = 0; i < noOfConnections; i++) {
068        Connection conn = ConnectionFactory.createConnection(conf);
069        connections[i] = conn;
070      }
071    }
072    createBatchPool(conf);
073  }
074
075  /**
076   * Close the open connections and shutdown the batchpool
077   */
078  public void close() {
079    synchronized (connectionsLock) {
080      if (connections != null) {
081        for (Connection conn : connections) {
082          if (conn != null) {
083            try {
084              conn.close();
085            } catch (IOException e) {
086              LOG.info("Got exception in closing connection", e);
087            } finally {
088              conn = null;
089            }
090          }
091        }
092        connections = null;
093      }
094    }
095    if (this.batchPool != null && !this.batchPool.isShutdown()) {
096      this.batchPool.shutdown();
097      try {
098        if (!this.batchPool.awaitTermination(10, TimeUnit.SECONDS)) {
099          this.batchPool.shutdownNow();
100        }
101      } catch (InterruptedException e) {
102        this.batchPool.shutdownNow();
103      }
104    }
105
106  }
107
108  /**
109   * Randomly pick a connection and process the batch of actions for a given table
110   * @param actions the actions
111   * @param tableName table name
112   * @param results the results array
113   * @param callback to run when results are in
114   * @throws IOException If IO failure occurs
115   */
116  @SuppressWarnings("deprecation")
117  public <R> void processBatchCallback(List<? extends Row> actions, TableName tableName,
118      Object[] results, Batch.Callback<R> callback) throws IOException {
119    // Currently used by RegionStateStore
120    ClusterConnection conn =
121      (ClusterConnection) connections[ThreadLocalRandom.current().nextInt(noOfConnections)];
122
123    HTable.doBatchWithCallback(actions, results, callback, conn, batchPool, tableName);
124  }
125
126  // Copied from ConnectionImplementation.getBatchPool()
127  // We should get rid of this when Connection.processBatchCallback is un-deprecated and provides
128  // an API to manage a batch pool
129  private void createBatchPool(Configuration conf) {
130    // Use the same config for keep alive as in ConnectionImplementation.getBatchPool();
131    int maxThreads = conf.getInt("hbase.multihconnection.threads.max", 256);
132    if (maxThreads == 0) {
133      maxThreads = Runtime.getRuntime().availableProcessors() * 8;
134    }
135    long keepAliveTime = conf.getLong("hbase.multihconnection.threads.keepalivetime", 60);
136    LinkedBlockingQueue<Runnable> workQueue =
137        new LinkedBlockingQueue<>(maxThreads
138            * conf.getInt(HConstants.HBASE_CLIENT_MAX_TOTAL_TASKS,
139              HConstants.DEFAULT_HBASE_CLIENT_MAX_TOTAL_TASKS));
140    ThreadPoolExecutor tpe =
141      new ThreadPoolExecutor(maxThreads, maxThreads, keepAliveTime, TimeUnit.SECONDS, workQueue,
142        new ThreadFactoryBuilder().setNameFormat("MultiHConnection" + "-shared-pool-%d")
143          .setUncaughtExceptionHandler(Threads.LOGGING_EXCEPTION_HANDLER).build());
144    tpe.allowCoreThreadTimeOut(true);
145    this.batchPool = tpe;
146  }
147  
148}