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.regionserver.wal; 019 020import java.io.IOException; 021import java.util.ArrayList; 022import java.util.List; 023import java.util.concurrent.Callable; 024import java.util.concurrent.ExecutorService; 025import java.util.concurrent.Executors; 026import java.util.concurrent.Future; 027import org.apache.hadoop.hbase.util.FutureUtils; 028import org.apache.hadoop.hbase.wal.WAL.Entry; 029import org.apache.hadoop.hbase.wal.WALProvider.Writer; 030import org.apache.yetus.audience.InterfaceAudience; 031 032import org.apache.hbase.thirdparty.com.google.common.collect.ImmutableList; 033import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder; 034 035@InterfaceAudience.Private 036public final class CombinedWriter extends CombinedWriterBase<Writer> implements Writer { 037 038 private final ImmutableList<ExecutorService> executors; 039 040 private CombinedWriter(ImmutableList<Writer> writers) { 041 super(writers); 042 ImmutableList.Builder<ExecutorService> builder = 043 ImmutableList.builderWithExpectedSize(writers.size() - 1); 044 for (int i = 0; i < writers.size() - 1; i++) { 045 Writer writer = writers.get(i); 046 builder.add(Executors.newSingleThreadExecutor(new ThreadFactoryBuilder() 047 .setNameFormat("WAL-Writer-" + writer + "-%d").setDaemon(true).build())); 048 } 049 this.executors = builder.build(); 050 } 051 052 private interface Action { 053 void action(Writer writer) throws IOException; 054 } 055 056 private void apply(Action action) throws IOException { 057 List<Future<?>> futures = new ArrayList<>(writers.size() - 1); 058 for (int i = 0; i < writers.size() - 1; i++) { 059 Writer writer = writers.get(i); 060 futures.add(executors.get(i).submit(new Callable<Void>() { 061 062 @Override 063 public Void call() throws Exception { 064 action.action(writer); 065 return null; 066 } 067 })); 068 } 069 action.action(writers.get(writers.size() - 1)); 070 for (Future<?> future : futures) { 071 FutureUtils.get(future); 072 } 073 } 074 075 @Override 076 public void sync(boolean forceSync) throws IOException { 077 apply(writer -> writer.sync(forceSync)); 078 } 079 080 @Override 081 public void append(Entry entry) throws IOException { 082 apply(writer -> writer.append(entry)); 083 } 084 085 @Override 086 public void close() throws IOException { 087 executors.forEach(ExecutorService::shutdown); 088 super.close(); 089 } 090 091 public static CombinedWriter create(Writer writer, Writer... writers) { 092 return new CombinedWriter(ImmutableList.<Writer> builder().add(writer).add(writers).build()); 093 } 094}