You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@hbase.apache.org by mi...@apache.org on 2016/02/03 18:26:10 UTC
[37/51] [partial] hbase-site git commit: Published site at
2f5767376f42c0416e025df412e3d5944a1b2a67.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/6a13df3e/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/FSHLog.RingBufferExceptionHandler.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/FSHLog.RingBufferExceptionHandler.html b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/FSHLog.RingBufferExceptionHandler.html
index c5c052a..036de4d 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/FSHLog.RingBufferExceptionHandler.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/FSHLog.RingBufferExceptionHandler.html
@@ -7,1999 +7,1998 @@
<body>
<div class="sourceContainer">
<pre><span class="sourceLineNo">001</span>/**<a name="line.1"></a>
-<span class="sourceLineNo">002</span><a name="line.2"></a>
-<span class="sourceLineNo">003</span> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.3"></a>
-<span class="sourceLineNo">004</span> * or more contributor license agreements. See the NOTICE file<a name="line.4"></a>
-<span class="sourceLineNo">005</span> * distributed with this work for additional information<a name="line.5"></a>
-<span class="sourceLineNo">006</span> * regarding copyright ownership. The ASF licenses this file<a name="line.6"></a>
-<span class="sourceLineNo">007</span> * to you under the Apache License, Version 2.0 (the<a name="line.7"></a>
-<span class="sourceLineNo">008</span> * "License"); you may not use this file except in compliance<a name="line.8"></a>
-<span class="sourceLineNo">009</span> * with the License. You may obtain a copy of the License at<a name="line.9"></a>
-<span class="sourceLineNo">010</span> *<a name="line.10"></a>
-<span class="sourceLineNo">011</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.11"></a>
-<span class="sourceLineNo">012</span> *<a name="line.12"></a>
-<span class="sourceLineNo">013</span> * Unless required by applicable law or agreed to in writing, software<a name="line.13"></a>
-<span class="sourceLineNo">014</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.14"></a>
-<span class="sourceLineNo">015</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.15"></a>
-<span class="sourceLineNo">016</span> * See the License for the specific language governing permissions and<a name="line.16"></a>
-<span class="sourceLineNo">017</span> * limitations under the License.<a name="line.17"></a>
-<span class="sourceLineNo">018</span> */<a name="line.18"></a>
-<span class="sourceLineNo">019</span>package org.apache.hadoop.hbase.regionserver.wal;<a name="line.19"></a>
-<span class="sourceLineNo">020</span><a name="line.20"></a>
-<span class="sourceLineNo">021</span>import static org.apache.hadoop.hbase.wal.DefaultWALProvider.WAL_FILE_NAME_DELIMITER;<a name="line.21"></a>
-<span class="sourceLineNo">022</span><a name="line.22"></a>
-<span class="sourceLineNo">023</span>import java.io.FileNotFoundException;<a name="line.23"></a>
-<span class="sourceLineNo">024</span>import java.io.IOException;<a name="line.24"></a>
-<span class="sourceLineNo">025</span>import java.io.InterruptedIOException;<a name="line.25"></a>
-<span class="sourceLineNo">026</span>import java.io.OutputStream;<a name="line.26"></a>
-<span class="sourceLineNo">027</span>import java.lang.management.ManagementFactory;<a name="line.27"></a>
-<span class="sourceLineNo">028</span>import java.lang.management.MemoryUsage;<a name="line.28"></a>
-<span class="sourceLineNo">029</span>import java.lang.reflect.InvocationTargetException;<a name="line.29"></a>
-<span class="sourceLineNo">030</span>import java.net.URLEncoder;<a name="line.30"></a>
-<span class="sourceLineNo">031</span>import java.util.ArrayList;<a name="line.31"></a>
-<span class="sourceLineNo">032</span>import java.util.Arrays;<a name="line.32"></a>
-<span class="sourceLineNo">033</span>import java.util.Comparator;<a name="line.33"></a>
-<span class="sourceLineNo">034</span>import java.util.List;<a name="line.34"></a>
-<span class="sourceLineNo">035</span>import java.util.Map;<a name="line.35"></a>
-<span class="sourceLineNo">036</span>import java.util.NavigableMap;<a name="line.36"></a>
-<span class="sourceLineNo">037</span>import java.util.Set;<a name="line.37"></a>
-<span class="sourceLineNo">038</span>import java.util.concurrent.BlockingQueue;<a name="line.38"></a>
-<span class="sourceLineNo">039</span>import java.util.concurrent.ConcurrentHashMap;<a name="line.39"></a>
-<span class="sourceLineNo">040</span>import java.util.concurrent.ConcurrentSkipListMap;<a name="line.40"></a>
-<span class="sourceLineNo">041</span>import java.util.concurrent.CopyOnWriteArrayList;<a name="line.41"></a>
-<span class="sourceLineNo">042</span>import java.util.concurrent.CountDownLatch;<a name="line.42"></a>
-<span class="sourceLineNo">043</span>import java.util.concurrent.ExecutionException;<a name="line.43"></a>
-<span class="sourceLineNo">044</span>import java.util.concurrent.ExecutorService;<a name="line.44"></a>
-<span class="sourceLineNo">045</span>import java.util.concurrent.Executors;<a name="line.45"></a>
-<span class="sourceLineNo">046</span>import java.util.concurrent.LinkedBlockingQueue;<a name="line.46"></a>
-<span class="sourceLineNo">047</span>import java.util.concurrent.TimeUnit;<a name="line.47"></a>
-<span class="sourceLineNo">048</span>import java.util.concurrent.atomic.AtomicBoolean;<a name="line.48"></a>
-<span class="sourceLineNo">049</span>import java.util.concurrent.atomic.AtomicInteger;<a name="line.49"></a>
-<span class="sourceLineNo">050</span>import java.util.concurrent.atomic.AtomicLong;<a name="line.50"></a>
-<span class="sourceLineNo">051</span>import java.util.concurrent.locks.ReentrantLock;<a name="line.51"></a>
-<span class="sourceLineNo">052</span><a name="line.52"></a>
-<span class="sourceLineNo">053</span>import org.apache.commons.logging.Log;<a name="line.53"></a>
-<span class="sourceLineNo">054</span>import org.apache.commons.logging.LogFactory;<a name="line.54"></a>
-<span class="sourceLineNo">055</span>import org.apache.hadoop.conf.Configuration;<a name="line.55"></a>
-<span class="sourceLineNo">056</span>import org.apache.hadoop.fs.FSDataOutputStream;<a name="line.56"></a>
-<span class="sourceLineNo">057</span>import org.apache.hadoop.fs.FileStatus;<a name="line.57"></a>
-<span class="sourceLineNo">058</span>import org.apache.hadoop.fs.FileSystem;<a name="line.58"></a>
-<span class="sourceLineNo">059</span>import org.apache.hadoop.fs.Path;<a name="line.59"></a>
-<span class="sourceLineNo">060</span>import org.apache.hadoop.fs.PathFilter;<a name="line.60"></a>
-<span class="sourceLineNo">061</span>import org.apache.hadoop.hbase.Cell;<a name="line.61"></a>
-<span class="sourceLineNo">062</span>import org.apache.hadoop.hbase.CellUtil;<a name="line.62"></a>
-<span class="sourceLineNo">063</span>import org.apache.hadoop.hbase.HBaseConfiguration;<a name="line.63"></a>
-<span class="sourceLineNo">064</span>import org.apache.hadoop.hbase.HConstants;<a name="line.64"></a>
-<span class="sourceLineNo">065</span>import org.apache.hadoop.hbase.HRegionInfo;<a name="line.65"></a>
-<span class="sourceLineNo">066</span>import org.apache.hadoop.hbase.HTableDescriptor;<a name="line.66"></a>
-<span class="sourceLineNo">067</span>import org.apache.hadoop.hbase.classification.InterfaceAudience;<a name="line.67"></a>
-<span class="sourceLineNo">068</span>import org.apache.hadoop.hbase.io.util.HeapMemorySizeUtil;<a name="line.68"></a>
-<span class="sourceLineNo">069</span>import org.apache.hadoop.hbase.util.Bytes;<a name="line.69"></a>
-<span class="sourceLineNo">070</span>import org.apache.hadoop.hbase.util.ClassSize;<a name="line.70"></a>
-<span class="sourceLineNo">071</span>import org.apache.hadoop.hbase.util.DrainBarrier;<a name="line.71"></a>
-<span class="sourceLineNo">072</span>import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;<a name="line.72"></a>
-<span class="sourceLineNo">073</span>import org.apache.hadoop.hbase.util.FSUtils;<a name="line.73"></a>
-<span class="sourceLineNo">074</span>import org.apache.hadoop.hbase.util.HasThread;<a name="line.74"></a>
-<span class="sourceLineNo">075</span>import org.apache.hadoop.hbase.util.Threads;<a name="line.75"></a>
-<span class="sourceLineNo">076</span>import org.apache.hadoop.hbase.wal.DefaultWALProvider;<a name="line.76"></a>
-<span class="sourceLineNo">077</span>import org.apache.hadoop.hbase.wal.WAL;<a name="line.77"></a>
-<span class="sourceLineNo">078</span>import org.apache.hadoop.hbase.wal.WALFactory;<a name="line.78"></a>
-<span class="sourceLineNo">079</span>import org.apache.hadoop.hbase.wal.WALKey;<a name="line.79"></a>
-<span class="sourceLineNo">080</span>import org.apache.hadoop.hbase.wal.WALPrettyPrinter;<a name="line.80"></a>
-<span class="sourceLineNo">081</span>import org.apache.hadoop.hbase.wal.WALProvider.Writer;<a name="line.81"></a>
-<span class="sourceLineNo">082</span>import org.apache.hadoop.hbase.wal.WALSplitter;<a name="line.82"></a>
-<span class="sourceLineNo">083</span>import org.apache.hadoop.hdfs.DFSOutputStream;<a name="line.83"></a>
-<span class="sourceLineNo">084</span>import org.apache.hadoop.hdfs.client.HdfsDataOutputStream;<a name="line.84"></a>
-<span class="sourceLineNo">085</span>import org.apache.hadoop.hdfs.protocol.DatanodeInfo;<a name="line.85"></a>
-<span class="sourceLineNo">086</span>import org.apache.hadoop.util.StringUtils;<a name="line.86"></a>
-<span class="sourceLineNo">087</span>import org.apache.htrace.NullScope;<a name="line.87"></a>
-<span class="sourceLineNo">088</span>import org.apache.htrace.Span;<a name="line.88"></a>
-<span class="sourceLineNo">089</span>import org.apache.htrace.Trace;<a name="line.89"></a>
-<span class="sourceLineNo">090</span>import org.apache.htrace.TraceScope;<a name="line.90"></a>
-<span class="sourceLineNo">091</span><a name="line.91"></a>
-<span class="sourceLineNo">092</span>import com.google.common.annotations.VisibleForTesting;<a name="line.92"></a>
-<span class="sourceLineNo">093</span>import com.lmax.disruptor.BlockingWaitStrategy;<a name="line.93"></a>
-<span class="sourceLineNo">094</span>import com.lmax.disruptor.EventHandler;<a name="line.94"></a>
-<span class="sourceLineNo">095</span>import com.lmax.disruptor.ExceptionHandler;<a name="line.95"></a>
-<span class="sourceLineNo">096</span>import com.lmax.disruptor.LifecycleAware;<a name="line.96"></a>
-<span class="sourceLineNo">097</span>import com.lmax.disruptor.TimeoutException;<a name="line.97"></a>
-<span class="sourceLineNo">098</span>import com.lmax.disruptor.dsl.Disruptor;<a name="line.98"></a>
-<span class="sourceLineNo">099</span>import com.lmax.disruptor.dsl.ProducerType;<a name="line.99"></a>
-<span class="sourceLineNo">100</span><a name="line.100"></a>
-<span class="sourceLineNo">101</span>/**<a name="line.101"></a>
-<span class="sourceLineNo">102</span> * Implementation of {@link WAL} to go against {@link FileSystem}; i.e. keep WALs in HDFS.<a name="line.102"></a>
-<span class="sourceLineNo">103</span> * Only one WAL is ever being written at a time. When a WAL hits a configured maximum size,<a name="line.103"></a>
-<span class="sourceLineNo">104</span> * it is rolled. This is done internal to the implementation.<a name="line.104"></a>
-<span class="sourceLineNo">105</span> *<a name="line.105"></a>
-<span class="sourceLineNo">106</span> * <p>As data is flushed from the MemStore to other on-disk structures (files sorted by<a name="line.106"></a>
-<span class="sourceLineNo">107</span> * key, hfiles), a WAL becomes obsolete. We can let go of all the log edits/entries for a given<a name="line.107"></a>
-<span class="sourceLineNo">108</span> * HRegion-sequence id. A bunch of work in the below is done keeping account of these region<a name="line.108"></a>
-<span class="sourceLineNo">109</span> * sequence ids -- what is flushed out to hfiles, and what is yet in WAL and in memory only.<a name="line.109"></a>
-<span class="sourceLineNo">110</span> *<a name="line.110"></a>
-<span class="sourceLineNo">111</span> * <p>It is only practical to delete entire files. Thus, we delete an entire on-disk file<a name="line.111"></a>
-<span class="sourceLineNo">112</span> * <code>F</code> when all of the edits in <code>F</code> have a log-sequence-id that's older<a name="line.112"></a>
-<span class="sourceLineNo">113</span> * (smaller) than the most-recent flush.<a name="line.113"></a>
-<span class="sourceLineNo">114</span> *<a name="line.114"></a>
-<span class="sourceLineNo">115</span> * <p>To read an WAL, call {@link WALFactory#createReader(org.apache.hadoop.fs.FileSystem,<a name="line.115"></a>
-<span class="sourceLineNo">116</span> * org.apache.hadoop.fs.Path)}.<a name="line.116"></a>
-<span class="sourceLineNo">117</span> *<a name="line.117"></a>
-<span class="sourceLineNo">118</span> * <h2>Failure Semantic</h2><a name="line.118"></a>
-<span class="sourceLineNo">119</span> * If an exception on append or sync, roll the WAL because the current WAL is now a lame duck;<a name="line.119"></a>
-<span class="sourceLineNo">120</span> * any more appends or syncs will fail also with the same original exception. If we have made<a name="line.120"></a>
-<span class="sourceLineNo">121</span> * successful appends to the WAL and we then are unable to sync them, our current semantic is to<a name="line.121"></a>
-<span class="sourceLineNo">122</span> * return error to the client that the appends failed but also to abort the current context,<a name="line.122"></a>
-<span class="sourceLineNo">123</span> * usually the hosting server. We need to replay the WALs. TODO: Change this semantic. A roll of<a name="line.123"></a>
-<span class="sourceLineNo">124</span> * WAL may be sufficient as long as we have flagged client that the append failed. TODO:<a name="line.124"></a>
-<span class="sourceLineNo">125</span> * replication may pick up these last edits though they have been marked as failed append (Need to<a name="line.125"></a>
-<span class="sourceLineNo">126</span> * keep our own file lengths, not rely on HDFS).<a name="line.126"></a>
-<span class="sourceLineNo">127</span> */<a name="line.127"></a>
-<span class="sourceLineNo">128</span>@InterfaceAudience.Private<a name="line.128"></a>
-<span class="sourceLineNo">129</span>public class FSHLog implements WAL {<a name="line.129"></a>
-<span class="sourceLineNo">130</span> // IMPLEMENTATION NOTES:<a name="line.130"></a>
-<span class="sourceLineNo">131</span> //<a name="line.131"></a>
-<span class="sourceLineNo">132</span> // At the core is a ring buffer. Our ring buffer is the LMAX Disruptor. It tries to<a name="line.132"></a>
-<span class="sourceLineNo">133</span> // minimize synchronizations and volatile writes when multiple contending threads as is the case<a name="line.133"></a>
-<span class="sourceLineNo">134</span> // here appending and syncing on a single WAL. The Disruptor is configured to handle multiple<a name="line.134"></a>
-<span class="sourceLineNo">135</span> // producers but it has one consumer only (the producers in HBase are IPC Handlers calling append<a name="line.135"></a>
-<span class="sourceLineNo">136</span> // and then sync). The single consumer/writer pulls the appends and syncs off the ring buffer.<a name="line.136"></a>
-<span class="sourceLineNo">137</span> // When a handler calls sync, it is given back a future. The producer 'blocks' on the future so<a name="line.137"></a>
-<span class="sourceLineNo">138</span> // it does not return until the sync completes. The future is passed over the ring buffer from<a name="line.138"></a>
-<span class="sourceLineNo">139</span> // the producer/handler to the consumer thread where it does its best to batch up the producer<a name="line.139"></a>
-<span class="sourceLineNo">140</span> // syncs so one WAL sync actually spans multiple producer sync invocations. How well the<a name="line.140"></a>
-<span class="sourceLineNo">141</span> // batching works depends on the write rate; i.e. we tend to batch more in times of<a name="line.141"></a>
-<span class="sourceLineNo">142</span> // high writes/syncs.<a name="line.142"></a>
-<span class="sourceLineNo">143</span> //<a name="line.143"></a>
-<span class="sourceLineNo">144</span> // Calls to append now also wait until the append has been done on the consumer side of the<a name="line.144"></a>
-<span class="sourceLineNo">145</span> // disruptor. We used to not wait but it makes the implemenation easier to grok if we have<a name="line.145"></a>
-<span class="sourceLineNo">146</span> // the region edit/sequence id after the append returns.<a name="line.146"></a>
-<span class="sourceLineNo">147</span> //<a name="line.147"></a>
-<span class="sourceLineNo">148</span> // TODO: Handlers need to coordinate appending AND syncing. Can we have the threads contend<a name="line.148"></a>
-<span class="sourceLineNo">149</span> // once only? Probably hard given syncs take way longer than an append.<a name="line.149"></a>
-<span class="sourceLineNo">150</span> //<a name="line.150"></a>
-<span class="sourceLineNo">151</span> // The consumer threads pass the syncs off to multiple syncing threads in a round robin fashion<a name="line.151"></a>
-<span class="sourceLineNo">152</span> // to ensure we keep up back-to-back FS sync calls (FS sync calls are the long poll writing the<a name="line.152"></a>
-<span class="sourceLineNo">153</span> // WAL). The consumer thread passes the futures to the sync threads for it to complete<a name="line.153"></a>
-<span class="sourceLineNo">154</span> // the futures when done.<a name="line.154"></a>
-<span class="sourceLineNo">155</span> //<a name="line.155"></a>
-<span class="sourceLineNo">156</span> // The 'sequence' in the below is the sequence of the append/sync on the ringbuffer. It<a name="line.156"></a>
-<span class="sourceLineNo">157</span> // acts as a sort-of transaction id. It is always incrementing.<a name="line.157"></a>
-<span class="sourceLineNo">158</span> //<a name="line.158"></a>
-<span class="sourceLineNo">159</span> // The RingBufferEventHandler class hosts the ring buffer consuming code. The threads that<a name="line.159"></a>
-<span class="sourceLineNo">160</span> // do the actual FS sync are implementations of SyncRunner. SafePointZigZagLatch is a<a name="line.160"></a>
-<span class="sourceLineNo">161</span> // synchronization class used to halt the consumer at a safe point -- just after all outstanding<a name="line.161"></a>
-<span class="sourceLineNo">162</span> // syncs and appends have completed -- so the log roller can swap the WAL out under it.<a name="line.162"></a>
-<span class="sourceLineNo">163</span><a name="line.163"></a>
-<span class="sourceLineNo">164</span> private static final Log LOG = LogFactory.getLog(FSHLog.class);<a name="line.164"></a>
-<span class="sourceLineNo">165</span><a name="line.165"></a>
-<span class="sourceLineNo">166</span> private static final int DEFAULT_SLOW_SYNC_TIME_MS = 100; // in ms<a name="line.166"></a>
-<span class="sourceLineNo">167</span><a name="line.167"></a>
-<span class="sourceLineNo">168</span> /**<a name="line.168"></a>
-<span class="sourceLineNo">169</span> * The nexus at which all incoming handlers meet. Does appends and sync with an ordering.<a name="line.169"></a>
-<span class="sourceLineNo">170</span> * Appends and syncs are each put on the ring which means handlers need to<a name="line.170"></a>
-<span class="sourceLineNo">171</span> * smash up against the ring twice (can we make it once only? ... maybe not since time to append<a name="line.171"></a>
-<span class="sourceLineNo">172</span> * is so different from time to sync and sometimes we don't want to sync or we want to async<a name="line.172"></a>
-<span class="sourceLineNo">173</span> * the sync). The ring is where we make sure of our ordering and it is also where we do<a name="line.173"></a>
-<span class="sourceLineNo">174</span> * batching up of handler sync calls.<a name="line.174"></a>
-<span class="sourceLineNo">175</span> */<a name="line.175"></a>
-<span class="sourceLineNo">176</span> private final Disruptor<RingBufferTruck> disruptor;<a name="line.176"></a>
-<span class="sourceLineNo">177</span><a name="line.177"></a>
-<span class="sourceLineNo">178</span> /**<a name="line.178"></a>
-<span class="sourceLineNo">179</span> * An executorservice that runs the disruptor AppendEventHandler append executor.<a name="line.179"></a>
-<span class="sourceLineNo">180</span> */<a name="line.180"></a>
-<span class="sourceLineNo">181</span> private final ExecutorService appendExecutor;<a name="line.181"></a>
-<span class="sourceLineNo">182</span><a name="line.182"></a>
-<span class="sourceLineNo">183</span> /**<a name="line.183"></a>
-<span class="sourceLineNo">184</span> * This fellow is run by the above appendExecutor service but it is all about batching up appends<a name="line.184"></a>
-<span class="sourceLineNo">185</span> * and syncs; it may shutdown without cleaning out the last few appends or syncs. To guard<a name="line.185"></a>
-<span class="sourceLineNo">186</span> * against this, keep a reference to this handler and do explicit close on way out to make sure<a name="line.186"></a>
-<span class="sourceLineNo">187</span> * all flushed out before we exit.<a name="line.187"></a>
-<span class="sourceLineNo">188</span> */<a name="line.188"></a>
-<span class="sourceLineNo">189</span> private final RingBufferEventHandler ringBufferEventHandler;<a name="line.189"></a>
-<span class="sourceLineNo">190</span><a name="line.190"></a>
-<span class="sourceLineNo">191</span> /**<a name="line.191"></a>
-<span class="sourceLineNo">192</span> * Map of {@link SyncFuture}s keyed by Handler objects. Used so we reuse SyncFutures.<a name="line.192"></a>
-<span class="sourceLineNo">193</span> * TODO: Reus FSWALEntry's rather than create them anew each time as we do SyncFutures here.<a name="line.193"></a>
-<span class="sourceLineNo">194</span> * TODO: Add a FSWalEntry and SyncFuture as thread locals on handlers rather than have them<a name="line.194"></a>
-<span class="sourceLineNo">195</span> * get them from this Map?<a name="line.195"></a>
-<span class="sourceLineNo">196</span> */<a name="line.196"></a>
-<span class="sourceLineNo">197</span> private final Map<Thread, SyncFuture> syncFuturesByHandler;<a name="line.197"></a>
-<span class="sourceLineNo">198</span><a name="line.198"></a>
-<span class="sourceLineNo">199</span> /**<a name="line.199"></a>
-<span class="sourceLineNo">200</span> * The highest known outstanding unsync'd WALEdit sequence number where sequence number is the<a name="line.200"></a>
-<span class="sourceLineNo">201</span> * ring buffer sequence. Maintained by the ring buffer consumer.<a name="line.201"></a>
-<span class="sourceLineNo">202</span> */<a name="line.202"></a>
-<span class="sourceLineNo">203</span> private volatile long highestUnsyncedSequence = -1;<a name="line.203"></a>
-<span class="sourceLineNo">204</span><a name="line.204"></a>
-<span class="sourceLineNo">205</span> /**<a name="line.205"></a>
-<span class="sourceLineNo">206</span> * Updated to the ring buffer sequence of the last successful sync call. This can be less than<a name="line.206"></a>
-<span class="sourceLineNo">207</span> * {@link #highestUnsyncedSequence} for case where we have an append where a sync has not yet<a name="line.207"></a>
-<span class="sourceLineNo">208</span> * come in for it. Maintained by the syncing threads.<a name="line.208"></a>
-<span class="sourceLineNo">209</span> */<a name="line.209"></a>
-<span class="sourceLineNo">210</span> private final AtomicLong highestSyncedSequence = new AtomicLong(0);<a name="line.210"></a>
-<span class="sourceLineNo">211</span><a name="line.211"></a>
-<span class="sourceLineNo">212</span> /**<a name="line.212"></a>
-<span class="sourceLineNo">213</span> * file system instance<a name="line.213"></a>
-<span class="sourceLineNo">214</span> */<a name="line.214"></a>
-<span class="sourceLineNo">215</span> protected final FileSystem fs;<a name="line.215"></a>
-<span class="sourceLineNo">216</span><a name="line.216"></a>
-<span class="sourceLineNo">217</span> /**<a name="line.217"></a>
-<span class="sourceLineNo">218</span> * WAL directory, where all WAL files would be placed.<a name="line.218"></a>
-<span class="sourceLineNo">219</span> */<a name="line.219"></a>
-<span class="sourceLineNo">220</span> private final Path fullPathLogDir;<a name="line.220"></a>
-<span class="sourceLineNo">221</span><a name="line.221"></a>
-<span class="sourceLineNo">222</span> /**<a name="line.222"></a>
-<span class="sourceLineNo">223</span> * dir path where old logs are kept.<a name="line.223"></a>
-<span class="sourceLineNo">224</span> */<a name="line.224"></a>
-<span class="sourceLineNo">225</span> private final Path fullPathArchiveDir;<a name="line.225"></a>
-<span class="sourceLineNo">226</span><a name="line.226"></a>
-<span class="sourceLineNo">227</span> /**<a name="line.227"></a>
-<span class="sourceLineNo">228</span> * Matches just those wal files that belong to this wal instance.<a name="line.228"></a>
-<span class="sourceLineNo">229</span> */<a name="line.229"></a>
-<span class="sourceLineNo">230</span> private final PathFilter ourFiles;<a name="line.230"></a>
-<span class="sourceLineNo">231</span><a name="line.231"></a>
-<span class="sourceLineNo">232</span> /**<a name="line.232"></a>
-<span class="sourceLineNo">233</span> * Prefix of a WAL file, usually the region server name it is hosted on.<a name="line.233"></a>
-<span class="sourceLineNo">234</span> */<a name="line.234"></a>
-<span class="sourceLineNo">235</span> private final String logFilePrefix;<a name="line.235"></a>
-<span class="sourceLineNo">236</span><a name="line.236"></a>
-<span class="sourceLineNo">237</span> /**<a name="line.237"></a>
-<span class="sourceLineNo">238</span> * Suffix included on generated wal file names<a name="line.238"></a>
-<span class="sourceLineNo">239</span> */<a name="line.239"></a>
-<span class="sourceLineNo">240</span> private final String logFileSuffix;<a name="line.240"></a>
-<span class="sourceLineNo">241</span><a name="line.241"></a>
-<span class="sourceLineNo">242</span> /**<a name="line.242"></a>
-<span class="sourceLineNo">243</span> * Prefix used when checking for wal membership.<a name="line.243"></a>
-<span class="sourceLineNo">244</span> */<a name="line.244"></a>
-<span class="sourceLineNo">245</span> private final String prefixPathStr;<a name="line.245"></a>
-<span class="sourceLineNo">246</span><a name="line.246"></a>
-<span class="sourceLineNo">247</span> private final WALCoprocessorHost coprocessorHost;<a name="line.247"></a>
-<span class="sourceLineNo">248</span><a name="line.248"></a>
-<span class="sourceLineNo">249</span> /**<a name="line.249"></a>
-<span class="sourceLineNo">250</span> * conf object<a name="line.250"></a>
-<span class="sourceLineNo">251</span> */<a name="line.251"></a>
-<span class="sourceLineNo">252</span> protected final Configuration conf;<a name="line.252"></a>
-<span class="sourceLineNo">253</span><a name="line.253"></a>
-<span class="sourceLineNo">254</span> /** Listeners that are called on WAL events. */<a name="line.254"></a>
-<span class="sourceLineNo">255</span> private final List<WALActionsListener> listeners =<a name="line.255"></a>
-<span class="sourceLineNo">256</span> new CopyOnWriteArrayList<WALActionsListener>();<a name="line.256"></a>
-<span class="sourceLineNo">257</span><a name="line.257"></a>
-<span class="sourceLineNo">258</span> @Override<a name="line.258"></a>
-<span class="sourceLineNo">259</span> public void registerWALActionsListener(final WALActionsListener listener) {<a name="line.259"></a>
-<span class="sourceLineNo">260</span> this.listeners.add(listener);<a name="line.260"></a>
-<span class="sourceLineNo">261</span> }<a name="line.261"></a>
-<span class="sourceLineNo">262</span><a name="line.262"></a>
-<span class="sourceLineNo">263</span> @Override<a name="line.263"></a>
-<span class="sourceLineNo">264</span> public boolean unregisterWALActionsListener(final WALActionsListener listener) {<a name="line.264"></a>
-<span class="sourceLineNo">265</span> return this.listeners.remove(listener);<a name="line.265"></a>
-<span class="sourceLineNo">266</span> }<a name="line.266"></a>
-<span class="sourceLineNo">267</span><a name="line.267"></a>
-<span class="sourceLineNo">268</span> @Override<a name="line.268"></a>
-<span class="sourceLineNo">269</span> public WALCoprocessorHost getCoprocessorHost() {<a name="line.269"></a>
-<span class="sourceLineNo">270</span> return coprocessorHost;<a name="line.270"></a>
-<span class="sourceLineNo">271</span> }<a name="line.271"></a>
-<span class="sourceLineNo">272</span><a name="line.272"></a>
-<span class="sourceLineNo">273</span> /**<a name="line.273"></a>
-<span class="sourceLineNo">274</span> * FSDataOutputStream associated with the current SequenceFile.writer<a name="line.274"></a>
-<span class="sourceLineNo">275</span> */<a name="line.275"></a>
-<span class="sourceLineNo">276</span> private FSDataOutputStream hdfs_out;<a name="line.276"></a>
-<span class="sourceLineNo">277</span><a name="line.277"></a>
-<span class="sourceLineNo">278</span> // All about log rolling if not enough replicas outstanding.<a name="line.278"></a>
-<span class="sourceLineNo">279</span><a name="line.279"></a>
-<span class="sourceLineNo">280</span> // Minimum tolerable replicas, if the actual value is lower than it, rollWriter will be triggered<a name="line.280"></a>
-<span class="sourceLineNo">281</span> private final int minTolerableReplication;<a name="line.281"></a>
-<span class="sourceLineNo">282</span><a name="line.282"></a>
-<span class="sourceLineNo">283</span> private final int slowSyncNs;<a name="line.283"></a>
-<span class="sourceLineNo">284</span><a name="line.284"></a>
-<span class="sourceLineNo">285</span> // If live datanode count is lower than the default replicas value,<a name="line.285"></a>
-<span class="sourceLineNo">286</span> // RollWriter will be triggered in each sync(So the RollWriter will be<a name="line.286"></a>
-<span class="sourceLineNo">287</span> // triggered one by one in a short time). Using it as a workaround to slow<a name="line.287"></a>
-<span class="sourceLineNo">288</span> // down the roll frequency triggered by checkLowReplication().<a name="line.288"></a>
-<span class="sourceLineNo">289</span> private final AtomicInteger consecutiveLogRolls = new AtomicInteger(0);<a name="line.289"></a>
-<span class="sourceLineNo">290</span><a name="line.290"></a>
-<span class="sourceLineNo">291</span> private final int lowReplicationRollLimit;<a name="line.291"></a>
-<span class="sourceLineNo">292</span><a name="line.292"></a>
-<span class="sourceLineNo">293</span> // If consecutiveLogRolls is larger than lowReplicationRollLimit,<a name="line.293"></a>
-<span class="sourceLineNo">294</span> // then disable the rolling in checkLowReplication().<a name="line.294"></a>
-<span class="sourceLineNo">295</span> // Enable it if the replications recover.<a name="line.295"></a>
-<span class="sourceLineNo">296</span> private volatile boolean lowReplicationRollEnabled = true;<a name="line.296"></a>
-<span class="sourceLineNo">297</span><a name="line.297"></a>
-<span class="sourceLineNo">298</span> /**<a name="line.298"></a>
-<span class="sourceLineNo">299</span> * Class that does accounting of sequenceids in WAL subsystem. Holds oldest outstanding<a name="line.299"></a>
-<span class="sourceLineNo">300</span> * sequence id as yet not flushed as well as the most recent edit sequence id appended to the<a name="line.300"></a>
-<span class="sourceLineNo">301</span> * WAL. Has facility for answering questions such as "Is it safe to GC a WAL?".<a name="line.301"></a>
-<span class="sourceLineNo">302</span> */<a name="line.302"></a>
-<span class="sourceLineNo">303</span> private SequenceIdAccounting sequenceIdAccounting = new SequenceIdAccounting();<a name="line.303"></a>
-<span class="sourceLineNo">304</span><a name="line.304"></a>
-<span class="sourceLineNo">305</span> /**<a name="line.305"></a>
-<span class="sourceLineNo">306</span> * Current log file.<a name="line.306"></a>
-<span class="sourceLineNo">307</span> */<a name="line.307"></a>
-<span class="sourceLineNo">308</span> volatile Writer writer;<a name="line.308"></a>
-<span class="sourceLineNo">309</span><a name="line.309"></a>
-<span class="sourceLineNo">310</span> /** The barrier used to ensure that close() waits for all log rolls and flushes to finish. */<a name="line.310"></a>
-<span class="sourceLineNo">311</span> private final DrainBarrier closeBarrier = new DrainBarrier();<a name="line.311"></a>
-<span class="sourceLineNo">312</span><a name="line.312"></a>
-<span class="sourceLineNo">313</span> /**<a name="line.313"></a>
-<span class="sourceLineNo">314</span> * This lock makes sure only one log roll runs at a time. Should not be taken while any other<a name="line.314"></a>
-<span class="sourceLineNo">315</span> * lock is held. We don't just use synchronized because that results in bogus and tedious<a name="line.315"></a>
-<span class="sourceLineNo">316</span> * findbugs warning when it thinks synchronized controls writer thread safety. It is held when<a name="line.316"></a>
-<span class="sourceLineNo">317</span> * we are actually rolling the log. It is checked when we are looking to see if we should roll<a name="line.317"></a>
-<span class="sourceLineNo">318</span> * the log or not.<a name="line.318"></a>
-<span class="sourceLineNo">319</span> */<a name="line.319"></a>
-<span class="sourceLineNo">320</span> private final ReentrantLock rollWriterLock = new ReentrantLock(true);<a name="line.320"></a>
-<span class="sourceLineNo">321</span><a name="line.321"></a>
-<span class="sourceLineNo">322</span> private volatile boolean closed = false;<a name="line.322"></a>
-<span class="sourceLineNo">323</span> private final AtomicBoolean shutdown = new AtomicBoolean(false);<a name="line.323"></a>
-<span class="sourceLineNo">324</span><a name="line.324"></a>
-<span class="sourceLineNo">325</span> // The timestamp (in ms) when the log file was created.<a name="line.325"></a>
-<span class="sourceLineNo">326</span> private final AtomicLong filenum = new AtomicLong(-1);<a name="line.326"></a>
-<span class="sourceLineNo">327</span><a name="line.327"></a>
-<span class="sourceLineNo">328</span> // Number of transactions in the current Wal.<a name="line.328"></a>
-<span class="sourceLineNo">329</span> private final AtomicInteger numEntries = new AtomicInteger(0);<a name="line.329"></a>
-<span class="sourceLineNo">330</span><a name="line.330"></a>
-<span class="sourceLineNo">331</span> // If > than this size, roll the log.<a name="line.331"></a>
-<span class="sourceLineNo">332</span> private final long logrollsize;<a name="line.332"></a>
-<span class="sourceLineNo">333</span><a name="line.333"></a>
-<span class="sourceLineNo">334</span> /**<a name="line.334"></a>
-<span class="sourceLineNo">335</span> * The total size of wal<a name="line.335"></a>
-<span class="sourceLineNo">336</span> */<a name="line.336"></a>
-<span class="sourceLineNo">337</span> private AtomicLong totalLogSize = new AtomicLong(0);<a name="line.337"></a>
-<span class="sourceLineNo">338</span><a name="line.338"></a>
-<span class="sourceLineNo">339</span> /*<a name="line.339"></a>
-<span class="sourceLineNo">340</span> * If more than this many logs, force flush of oldest region to oldest edit<a name="line.340"></a>
-<span class="sourceLineNo">341</span> * goes to disk. If too many and we crash, then will take forever replaying.<a name="line.341"></a>
-<span class="sourceLineNo">342</span> * Keep the number of logs tidy.<a name="line.342"></a>
-<span class="sourceLineNo">343</span> */<a name="line.343"></a>
-<span class="sourceLineNo">344</span> private final int maxLogs;<a name="line.344"></a>
-<span class="sourceLineNo">345</span><a name="line.345"></a>
-<span class="sourceLineNo">346</span> /** Number of log close errors tolerated before we abort */<a name="line.346"></a>
-<span class="sourceLineNo">347</span> private final int closeErrorsTolerated;<a name="line.347"></a>
-<span class="sourceLineNo">348</span><a name="line.348"></a>
-<span class="sourceLineNo">349</span> private final AtomicInteger closeErrorCount = new AtomicInteger();<a name="line.349"></a>
+<span class="sourceLineNo">002</span> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
+<span class="sourceLineNo">003</span> * or more contributor license agreements. See the NOTICE file<a name="line.3"></a>
+<span class="sourceLineNo">004</span> * distributed with this work for additional information<a name="line.4"></a>
+<span class="sourceLineNo">005</span> * regarding copyright ownership. The ASF licenses this file<a name="line.5"></a>
+<span class="sourceLineNo">006</span> * to you under the Apache License, Version 2.0 (the<a name="line.6"></a>
+<span class="sourceLineNo">007</span> * "License"); you may not use this file except in compliance<a name="line.7"></a>
+<span class="sourceLineNo">008</span> * with the License. You may obtain a copy of the License at<a name="line.8"></a>
+<span class="sourceLineNo">009</span> *<a name="line.9"></a>
+<span class="sourceLineNo">010</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
+<span class="sourceLineNo">011</span> *<a name="line.11"></a>
+<span class="sourceLineNo">012</span> * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a>
+<span class="sourceLineNo">013</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a>
+<span class="sourceLineNo">014</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a>
+<span class="sourceLineNo">015</span> * See the License for the specific language governing permissions and<a name="line.15"></a>
+<span class="sourceLineNo">016</span> * limitations under the License.<a name="line.16"></a>
+<span class="sourceLineNo">017</span> */<a name="line.17"></a>
+<span class="sourceLineNo">018</span>package org.apache.hadoop.hbase.regionserver.wal;<a name="line.18"></a>
+<span class="sourceLineNo">019</span><a name="line.19"></a>
+<span class="sourceLineNo">020</span>import static org.apache.hadoop.hbase.wal.DefaultWALProvider.WAL_FILE_NAME_DELIMITER;<a name="line.20"></a>
+<span class="sourceLineNo">021</span><a name="line.21"></a>
+<span class="sourceLineNo">022</span>import java.io.FileNotFoundException;<a name="line.22"></a>
+<span class="sourceLineNo">023</span>import java.io.IOException;<a name="line.23"></a>
+<span class="sourceLineNo">024</span>import java.io.InterruptedIOException;<a name="line.24"></a>
+<span class="sourceLineNo">025</span>import java.io.OutputStream;<a name="line.25"></a>
+<span class="sourceLineNo">026</span>import java.lang.management.ManagementFactory;<a name="line.26"></a>
+<span class="sourceLineNo">027</span>import java.lang.management.MemoryUsage;<a name="line.27"></a>
+<span class="sourceLineNo">028</span>import java.lang.reflect.InvocationTargetException;<a name="line.28"></a>
+<span class="sourceLineNo">029</span>import java.net.URLEncoder;<a name="line.29"></a>
+<span class="sourceLineNo">030</span>import java.util.ArrayList;<a name="line.30"></a>
+<span class="sourceLineNo">031</span>import java.util.Arrays;<a name="line.31"></a>
+<span class="sourceLineNo">032</span>import java.util.Comparator;<a name="line.32"></a>
+<span class="sourceLineNo">033</span>import java.util.List;<a name="line.33"></a>
+<span class="sourceLineNo">034</span>import java.util.Map;<a name="line.34"></a>
+<span class="sourceLineNo">035</span>import java.util.NavigableMap;<a name="line.35"></a>
+<span class="sourceLineNo">036</span>import java.util.Set;<a name="line.36"></a>
+<span class="sourceLineNo">037</span>import java.util.concurrent.BlockingQueue;<a name="line.37"></a>
+<span class="sourceLineNo">038</span>import java.util.concurrent.ConcurrentHashMap;<a name="line.38"></a>
+<span class="sourceLineNo">039</span>import java.util.concurrent.ConcurrentSkipListMap;<a name="line.39"></a>
+<span class="sourceLineNo">040</span>import java.util.concurrent.CopyOnWriteArrayList;<a name="line.40"></a>
+<span class="sourceLineNo">041</span>import java.util.concurrent.CountDownLatch;<a name="line.41"></a>
+<span class="sourceLineNo">042</span>import java.util.concurrent.ExecutionException;<a name="line.42"></a>
+<span class="sourceLineNo">043</span>import java.util.concurrent.ExecutorService;<a name="line.43"></a>
+<span class="sourceLineNo">044</span>import java.util.concurrent.Executors;<a name="line.44"></a>
+<span class="sourceLineNo">045</span>import java.util.concurrent.LinkedBlockingQueue;<a name="line.45"></a>
+<span class="sourceLineNo">046</span>import java.util.concurrent.TimeUnit;<a name="line.46"></a>
+<span class="sourceLineNo">047</span>import java.util.concurrent.atomic.AtomicBoolean;<a name="line.47"></a>
+<span class="sourceLineNo">048</span>import java.util.concurrent.atomic.AtomicInteger;<a name="line.48"></a>
+<span class="sourceLineNo">049</span>import java.util.concurrent.atomic.AtomicLong;<a name="line.49"></a>
+<span class="sourceLineNo">050</span>import java.util.concurrent.locks.ReentrantLock;<a name="line.50"></a>
+<span class="sourceLineNo">051</span><a name="line.51"></a>
+<span class="sourceLineNo">052</span>import org.apache.commons.logging.Log;<a name="line.52"></a>
+<span class="sourceLineNo">053</span>import org.apache.commons.logging.LogFactory;<a name="line.53"></a>
+<span class="sourceLineNo">054</span>import org.apache.hadoop.conf.Configuration;<a name="line.54"></a>
+<span class="sourceLineNo">055</span>import org.apache.hadoop.fs.FSDataOutputStream;<a name="line.55"></a>
+<span class="sourceLineNo">056</span>import org.apache.hadoop.fs.FileStatus;<a name="line.56"></a>
+<span class="sourceLineNo">057</span>import org.apache.hadoop.fs.FileSystem;<a name="line.57"></a>
+<span class="sourceLineNo">058</span>import org.apache.hadoop.fs.Path;<a name="line.58"></a>
+<span class="sourceLineNo">059</span>import org.apache.hadoop.fs.PathFilter;<a name="line.59"></a>
+<span class="sourceLineNo">060</span>import org.apache.hadoop.hbase.Cell;<a name="line.60"></a>
+<span class="sourceLineNo">061</span>import org.apache.hadoop.hbase.CellUtil;<a name="line.61"></a>
+<span class="sourceLineNo">062</span>import org.apache.hadoop.hbase.HBaseConfiguration;<a name="line.62"></a>
+<span class="sourceLineNo">063</span>import org.apache.hadoop.hbase.HConstants;<a name="line.63"></a>
+<span class="sourceLineNo">064</span>import org.apache.hadoop.hbase.HRegionInfo;<a name="line.64"></a>
+<span class="sourceLineNo">065</span>import org.apache.hadoop.hbase.HTableDescriptor;<a name="line.65"></a>
+<span class="sourceLineNo">066</span>import org.apache.hadoop.hbase.classification.InterfaceAudience;<a name="line.66"></a>
+<span class="sourceLineNo">067</span>import org.apache.hadoop.hbase.io.util.HeapMemorySizeUtil;<a name="line.67"></a>
+<span class="sourceLineNo">068</span>import org.apache.hadoop.hbase.util.Bytes;<a name="line.68"></a>
+<span class="sourceLineNo">069</span>import org.apache.hadoop.hbase.util.ClassSize;<a name="line.69"></a>
+<span class="sourceLineNo">070</span>import org.apache.hadoop.hbase.util.DrainBarrier;<a name="line.70"></a>
+<span class="sourceLineNo">071</span>import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;<a name="line.71"></a>
+<span class="sourceLineNo">072</span>import org.apache.hadoop.hbase.util.FSUtils;<a name="line.72"></a>
+<span class="sourceLineNo">073</span>import org.apache.hadoop.hbase.util.HasThread;<a name="line.73"></a>
+<span class="sourceLineNo">074</span>import org.apache.hadoop.hbase.util.Threads;<a name="line.74"></a>
+<span class="sourceLineNo">075</span>import org.apache.hadoop.hbase.wal.DefaultWALProvider;<a name="line.75"></a>
+<span class="sourceLineNo">076</span>import org.apache.hadoop.hbase.wal.WAL;<a name="line.76"></a>
+<span class="sourceLineNo">077</span>import org.apache.hadoop.hbase.wal.WALFactory;<a name="line.77"></a>
+<span class="sourceLineNo">078</span>import org.apache.hadoop.hbase.wal.WALKey;<a name="line.78"></a>
+<span class="sourceLineNo">079</span>import org.apache.hadoop.hbase.wal.WALPrettyPrinter;<a name="line.79"></a>
+<span class="sourceLineNo">080</span>import org.apache.hadoop.hbase.wal.WALProvider.Writer;<a name="line.80"></a>
+<span class="sourceLineNo">081</span>import org.apache.hadoop.hbase.wal.WALSplitter;<a name="line.81"></a>
+<span class="sourceLineNo">082</span>import org.apache.hadoop.hdfs.DFSOutputStream;<a name="line.82"></a>
+<span class="sourceLineNo">083</span>import org.apache.hadoop.hdfs.client.HdfsDataOutputStream;<a name="line.83"></a>
+<span class="sourceLineNo">084</span>import org.apache.hadoop.hdfs.protocol.DatanodeInfo;<a name="line.84"></a>
+<span class="sourceLineNo">085</span>import org.apache.hadoop.util.StringUtils;<a name="line.85"></a>
+<span class="sourceLineNo">086</span>import org.apache.htrace.NullScope;<a name="line.86"></a>
+<span class="sourceLineNo">087</span>import org.apache.htrace.Span;<a name="line.87"></a>
+<span class="sourceLineNo">088</span>import org.apache.htrace.Trace;<a name="line.88"></a>
+<span class="sourceLineNo">089</span>import org.apache.htrace.TraceScope;<a name="line.89"></a>
+<span class="sourceLineNo">090</span><a name="line.90"></a>
+<span class="sourceLineNo">091</span>import com.google.common.annotations.VisibleForTesting;<a name="line.91"></a>
+<span class="sourceLineNo">092</span>import com.lmax.disruptor.BlockingWaitStrategy;<a name="line.92"></a>
+<span class="sourceLineNo">093</span>import com.lmax.disruptor.EventHandler;<a name="line.93"></a>
+<span class="sourceLineNo">094</span>import com.lmax.disruptor.ExceptionHandler;<a name="line.94"></a>
+<span class="sourceLineNo">095</span>import com.lmax.disruptor.LifecycleAware;<a name="line.95"></a>
+<span class="sourceLineNo">096</span>import com.lmax.disruptor.TimeoutException;<a name="line.96"></a>
+<span class="sourceLineNo">097</span>import com.lmax.disruptor.dsl.Disruptor;<a name="line.97"></a>
+<span class="sourceLineNo">098</span>import com.lmax.disruptor.dsl.ProducerType;<a name="line.98"></a>
+<span class="sourceLineNo">099</span><a name="line.99"></a>
+<span class="sourceLineNo">100</span>/**<a name="line.100"></a>
+<span class="sourceLineNo">101</span> * Implementation of {@link WAL} to go against {@link FileSystem}; i.e. keep WALs in HDFS.<a name="line.101"></a>
+<span class="sourceLineNo">102</span> * Only one WAL is ever being written at a time. When a WAL hits a configured maximum size,<a name="line.102"></a>
+<span class="sourceLineNo">103</span> * it is rolled. This is done internal to the implementation.<a name="line.103"></a>
+<span class="sourceLineNo">104</span> *<a name="line.104"></a>
+<span class="sourceLineNo">105</span> * <p>As data is flushed from the MemStore to other on-disk structures (files sorted by<a name="line.105"></a>
+<span class="sourceLineNo">106</span> * key, hfiles), a WAL becomes obsolete. We can let go of all the log edits/entries for a given<a name="line.106"></a>
+<span class="sourceLineNo">107</span> * HRegion-sequence id. A bunch of work in the below is done keeping account of these region<a name="line.107"></a>
+<span class="sourceLineNo">108</span> * sequence ids -- what is flushed out to hfiles, and what is yet in WAL and in memory only.<a name="line.108"></a>
+<span class="sourceLineNo">109</span> *<a name="line.109"></a>
+<span class="sourceLineNo">110</span> * <p>It is only practical to delete entire files. Thus, we delete an entire on-disk file<a name="line.110"></a>
+<span class="sourceLineNo">111</span> * <code>F</code> when all of the edits in <code>F</code> have a log-sequence-id that's older<a name="line.111"></a>
+<span class="sourceLineNo">112</span> * (smaller) than the most-recent flush.<a name="line.112"></a>
+<span class="sourceLineNo">113</span> *<a name="line.113"></a>
+<span class="sourceLineNo">114</span> * <p>To read an WAL, call {@link WALFactory#createReader(org.apache.hadoop.fs.FileSystem,<a name="line.114"></a>
+<span class="sourceLineNo">115</span> * org.apache.hadoop.fs.Path)}.<a name="line.115"></a>
+<span class="sourceLineNo">116</span> *<a name="line.116"></a>
+<span class="sourceLineNo">117</span> * <h2>Failure Semantic</h2><a name="line.117"></a>
+<span class="sourceLineNo">118</span> * If an exception on append or sync, roll the WAL because the current WAL is now a lame duck;<a name="line.118"></a>
+<span class="sourceLineNo">119</span> * any more appends or syncs will fail also with the same original exception. If we have made<a name="line.119"></a>
+<span class="sourceLineNo">120</span> * successful appends to the WAL and we then are unable to sync them, our current semantic is to<a name="line.120"></a>
+<span class="sourceLineNo">121</span> * return error to the client that the appends failed but also to abort the current context,<a name="line.121"></a>
+<span class="sourceLineNo">122</span> * usually the hosting server. We need to replay the WALs. TODO: Change this semantic. A roll of<a name="line.122"></a>
+<span class="sourceLineNo">123</span> * WAL may be sufficient as long as we have flagged client that the append failed. TODO:<a name="line.123"></a>
+<span class="sourceLineNo">124</span> * replication may pick up these last edits though they have been marked as failed append (Need to<a name="line.124"></a>
+<span class="sourceLineNo">125</span> * keep our own file lengths, not rely on HDFS).<a name="line.125"></a>
+<span class="sourceLineNo">126</span> */<a name="line.126"></a>
+<span class="sourceLineNo">127</span>@InterfaceAudience.Private<a name="line.127"></a>
+<span class="sourceLineNo">128</span>public class FSHLog implements WAL {<a name="line.128"></a>
+<span class="sourceLineNo">129</span> // IMPLEMENTATION NOTES:<a name="line.129"></a>
+<span class="sourceLineNo">130</span> //<a name="line.130"></a>
+<span class="sourceLineNo">131</span> // At the core is a ring buffer. Our ring buffer is the LMAX Disruptor. It tries to<a name="line.131"></a>
+<span class="sourceLineNo">132</span> // minimize synchronizations and volatile writes when multiple contending threads as is the case<a name="line.132"></a>
+<span class="sourceLineNo">133</span> // here appending and syncing on a single WAL. The Disruptor is configured to handle multiple<a name="line.133"></a>
+<span class="sourceLineNo">134</span> // producers but it has one consumer only (the producers in HBase are IPC Handlers calling append<a name="line.134"></a>
+<span class="sourceLineNo">135</span> // and then sync). The single consumer/writer pulls the appends and syncs off the ring buffer.<a name="line.135"></a>
+<span class="sourceLineNo">136</span> // When a handler calls sync, it is given back a future. The producer 'blocks' on the future so<a name="line.136"></a>
+<span class="sourceLineNo">137</span> // it does not return until the sync completes. The future is passed over the ring buffer from<a name="line.137"></a>
+<span class="sourceLineNo">138</span> // the producer/handler to the consumer thread where it does its best to batch up the producer<a name="line.138"></a>
+<span class="sourceLineNo">139</span> // syncs so one WAL sync actually spans multiple producer sync invocations. How well the<a name="line.139"></a>
+<span class="sourceLineNo">140</span> // batching works depends on the write rate; i.e. we tend to batch more in times of<a name="line.140"></a>
+<span class="sourceLineNo">141</span> // high writes/syncs.<a name="line.141"></a>
+<span class="sourceLineNo">142</span> //<a name="line.142"></a>
+<span class="sourceLineNo">143</span> // Calls to append now also wait until the append has been done on the consumer side of the<a name="line.143"></a>
+<span class="sourceLineNo">144</span> // disruptor. We used to not wait but it makes the implemenation easier to grok if we have<a name="line.144"></a>
+<span class="sourceLineNo">145</span> // the region edit/sequence id after the append returns.<a name="line.145"></a>
+<span class="sourceLineNo">146</span> //<a name="line.146"></a>
+<span class="sourceLineNo">147</span> // TODO: Handlers need to coordinate appending AND syncing. Can we have the threads contend<a name="line.147"></a>
+<span class="sourceLineNo">148</span> // once only? Probably hard given syncs take way longer than an append.<a name="line.148"></a>
+<span class="sourceLineNo">149</span> //<a name="line.149"></a>
+<span class="sourceLineNo">150</span> // The consumer threads pass the syncs off to multiple syncing threads in a round robin fashion<a name="line.150"></a>
+<span class="sourceLineNo">151</span> // to ensure we keep up back-to-back FS sync calls (FS sync calls are the long poll writing the<a name="line.151"></a>
+<span class="sourceLineNo">152</span> // WAL). The consumer thread passes the futures to the sync threads for it to complete<a name="line.152"></a>
+<span class="sourceLineNo">153</span> // the futures when done.<a name="line.153"></a>
+<span class="sourceLineNo">154</span> //<a name="line.154"></a>
+<span class="sourceLineNo">155</span> // The 'sequence' in the below is the sequence of the append/sync on the ringbuffer. It<a name="line.155"></a>
+<span class="sourceLineNo">156</span> // acts as a sort-of transaction id. It is always incrementing.<a name="line.156"></a>
+<span class="sourceLineNo">157</span> //<a name="line.157"></a>
+<span class="sourceLineNo">158</span> // The RingBufferEventHandler class hosts the ring buffer consuming code. The threads that<a name="line.158"></a>
+<span class="sourceLineNo">159</span> // do the actual FS sync are implementations of SyncRunner. SafePointZigZagLatch is a<a name="line.159"></a>
+<span class="sourceLineNo">160</span> // synchronization class used to halt the consumer at a safe point -- just after all outstanding<a name="line.160"></a>
+<span class="sourceLineNo">161</span> // syncs and appends have completed -- so the log roller can swap the WAL out under it.<a name="line.161"></a>
+<span class="sourceLineNo">162</span><a name="line.162"></a>
+<span class="sourceLineNo">163</span> private static final Log LOG = LogFactory.getLog(FSHLog.class);<a name="line.163"></a>
+<span class="sourceLineNo">164</span><a name="line.164"></a>
+<span class="sourceLineNo">165</span> private static final int DEFAULT_SLOW_SYNC_TIME_MS = 100; // in ms<a name="line.165"></a>
+<span class="sourceLineNo">166</span><a name="line.166"></a>
+<span class="sourceLineNo">167</span> /**<a name="line.167"></a>
+<span class="sourceLineNo">168</span> * The nexus at which all incoming handlers meet. Does appends and sync with an ordering.<a name="line.168"></a>
+<span class="sourceLineNo">169</span> * Appends and syncs are each put on the ring which means handlers need to<a name="line.169"></a>
+<span class="sourceLineNo">170</span> * smash up against the ring twice (can we make it once only? ... maybe not since time to append<a name="line.170"></a>
+<span class="sourceLineNo">171</span> * is so different from time to sync and sometimes we don't want to sync or we want to async<a name="line.171"></a>
+<span class="sourceLineNo">172</span> * the sync). The ring is where we make sure of our ordering and it is also where we do<a name="line.172"></a>
+<span class="sourceLineNo">173</span> * batching up of handler sync calls.<a name="line.173"></a>
+<span class="sourceLineNo">174</span> */<a name="line.174"></a>
+<span class="sourceLineNo">175</span> private final Disruptor<RingBufferTruck> disruptor;<a name="line.175"></a>
+<span class="sourceLineNo">176</span><a name="line.176"></a>
+<span class="sourceLineNo">177</span> /**<a name="line.177"></a>
+<span class="sourceLineNo">178</span> * An executorservice that runs the disruptor AppendEventHandler append executor.<a name="line.178"></a>
+<span class="sourceLineNo">179</span> */<a name="line.179"></a>
+<span class="sourceLineNo">180</span> private final ExecutorService appendExecutor;<a name="line.180"></a>
+<span class="sourceLineNo">181</span><a name="line.181"></a>
+<span class="sourceLineNo">182</span> /**<a name="line.182"></a>
+<span class="sourceLineNo">183</span> * This fellow is run by the above appendExecutor service but it is all about batching up appends<a name="line.183"></a>
+<span class="sourceLineNo">184</span> * and syncs; it may shutdown without cleaning out the last few appends or syncs. To guard<a name="line.184"></a>
+<span class="sourceLineNo">185</span> * against this, keep a reference to this handler and do explicit close on way out to make sure<a name="line.185"></a>
+<span class="sourceLineNo">186</span> * all flushed out before we exit.<a name="line.186"></a>
+<span class="sourceLineNo">187</span> */<a name="line.187"></a>
+<span class="sourceLineNo">188</span> private final RingBufferEventHandler ringBufferEventHandler;<a name="line.188"></a>
+<span class="sourceLineNo">189</span><a name="line.189"></a>
+<span class="sourceLineNo">190</span> /**<a name="line.190"></a>
+<span class="sourceLineNo">191</span> * Map of {@link SyncFuture}s keyed by Handler objects. Used so we reuse SyncFutures.<a name="line.191"></a>
+<span class="sourceLineNo">192</span> * TODO: Reus FSWALEntry's rather than create them anew each time as we do SyncFutures here.<a name="line.192"></a>
+<span class="sourceLineNo">193</span> * TODO: Add a FSWalEntry and SyncFuture as thread locals on handlers rather than have them<a name="line.193"></a>
+<span class="sourceLineNo">194</span> * get them from this Map?<a name="line.194"></a>
+<span class="sourceLineNo">195</span> */<a name="line.195"></a>
+<span class="sourceLineNo">196</span> private final Map<Thread, SyncFuture> syncFuturesByHandler;<a name="line.196"></a>
+<span class="sourceLineNo">197</span><a name="line.197"></a>
+<span class="sourceLineNo">198</span> /**<a name="line.198"></a>
+<span class="sourceLineNo">199</span> * The highest known outstanding unsync'd WALEdit sequence number where sequence number is the<a name="line.199"></a>
+<span class="sourceLineNo">200</span> * ring buffer sequence. Maintained by the ring buffer consumer.<a name="line.200"></a>
+<span class="sourceLineNo">201</span> */<a name="line.201"></a>
+<span class="sourceLineNo">202</span> private volatile long highestUnsyncedSequence = -1;<a name="line.202"></a>
+<span class="sourceLineNo">203</span><a name="line.203"></a>
+<span class="sourceLineNo">204</span> /**<a name="line.204"></a>
+<span class="sourceLineNo">205</span> * Updated to the ring buffer sequence of the last successful sync call. This can be less than<a name="line.205"></a>
+<span class="sourceLineNo">206</span> * {@link #highestUnsyncedSequence} for case where we have an append where a sync has not yet<a name="line.206"></a>
+<span class="sourceLineNo">207</span> * come in for it. Maintained by the syncing threads.<a name="line.207"></a>
+<span class="sourceLineNo">208</span> */<a name="line.208"></a>
+<span class="sourceLineNo">209</span> private final AtomicLong highestSyncedSequence = new AtomicLong(0);<a name="line.209"></a>
+<span class="sourceLineNo">210</span><a name="line.210"></a>
+<span class="sourceLineNo">211</span> /**<a name="line.211"></a>
+<span class="sourceLineNo">212</span> * file system instance<a name="line.212"></a>
+<span class="sourceLineNo">213</span> */<a name="line.213"></a>
+<span class="sourceLineNo">214</span> protected final FileSystem fs;<a name="line.214"></a>
+<span class="sourceLineNo">215</span><a name="line.215"></a>
+<span class="sourceLineNo">216</span> /**<a name="line.216"></a>
+<span class="sourceLineNo">217</span> * WAL directory, where all WAL files would be placed.<a name="line.217"></a>
+<span class="sourceLineNo">218</span> */<a name="line.218"></a>
+<span class="sourceLineNo">219</span> private final Path fullPathLogDir;<a name="line.219"></a>
+<span class="sourceLineNo">220</span><a name="line.220"></a>
+<span class="sourceLineNo">221</span> /**<a name="line.221"></a>
+<span class="sourceLineNo">222</span> * dir path where old logs are kept.<a name="line.222"></a>
+<span class="sourceLineNo">223</span> */<a name="line.223"></a>
+<span class="sourceLineNo">224</span> private final Path fullPathArchiveDir;<a name="line.224"></a>
+<span class="sourceLineNo">225</span><a name="line.225"></a>
+<span class="sourceLineNo">226</span> /**<a name="line.226"></a>
+<span class="sourceLineNo">227</span> * Matches just those wal files that belong to this wal instance.<a name="line.227"></a>
+<span class="sourceLineNo">228</span> */<a name="line.228"></a>
+<span class="sourceLineNo">229</span> private final PathFilter ourFiles;<a name="line.229"></a>
+<span class="sourceLineNo">230</span><a name="line.230"></a>
+<span class="sourceLineNo">231</span> /**<a name="line.231"></a>
+<span class="sourceLineNo">232</span> * Prefix of a WAL file, usually the region server name it is hosted on.<a name="line.232"></a>
+<span class="sourceLineNo">233</span> */<a name="line.233"></a>
+<span class="sourceLineNo">234</span> private final String logFilePrefix;<a name="line.234"></a>
+<span class="sourceLineNo">235</span><a name="line.235"></a>
+<span class="sourceLineNo">236</span> /**<a name="line.236"></a>
+<span class="sourceLineNo">237</span> * Suffix included on generated wal file names<a name="line.237"></a>
+<span class="sourceLineNo">238</span> */<a name="line.238"></a>
+<span class="sourceLineNo">239</span> private final String logFileSuffix;<a name="line.239"></a>
+<span class="sourceLineNo">240</span><a name="line.240"></a>
+<span class="sourceLineNo">241</span> /**<a name="line.241"></a>
+<span class="sourceLineNo">242</span> * Prefix used when checking for wal membership.<a name="line.242"></a>
+<span class="sourceLineNo">243</span> */<a name="line.243"></a>
+<span class="sourceLineNo">244</span> private final String prefixPathStr;<a name="line.244"></a>
+<span class="sourceLineNo">245</span><a name="line.245"></a>
+<span class="sourceLineNo">246</span> private final WALCoprocessorHost coprocessorHost;<a name="line.246"></a>
+<span class="sourceLineNo">247</span><a name="line.247"></a>
+<span class="sourceLineNo">248</span> /**<a name="line.248"></a>
+<span class="sourceLineNo">249</span> * conf object<a name="line.249"></a>
+<span class="sourceLineNo">250</span> */<a name="line.250"></a>
+<span class="sourceLineNo">251</span> protected final Configuration conf;<a name="line.251"></a>
+<span class="sourceLineNo">252</span><a name="line.252"></a>
+<span class="sourceLineNo">253</span> /** Listeners that are called on WAL events. */<a name="line.253"></a>
+<span class="sourceLineNo">254</span> private final List<WALActionsListener> listeners =<a name="line.254"></a>
+<span class="sourceLineNo">255</span> new CopyOnWriteArrayList<WALActionsListener>();<a name="line.255"></a>
+<span class="sourceLineNo">256</span><a name="line.256"></a>
+<span class="sourceLineNo">257</span> @Override<a name="line.257"></a>
+<span class="sourceLineNo">258</span> public void registerWALActionsListener(final WALActionsListener listener) {<a name="line.258"></a>
+<span class="sourceLineNo">259</span> this.listeners.add(listener);<a name="line.259"></a>
+<span class="sourceLineNo">260</span> }<a name="line.260"></a>
+<span class="sourceLineNo">261</span><a name="line.261"></a>
+<span class="sourceLineNo">262</span> @Override<a name="line.262"></a>
+<span class="sourceLineNo">263</span> public boolean unregisterWALActionsListener(final WALActionsListener listener) {<a name="line.263"></a>
+<span class="sourceLineNo">264</span> return this.listeners.remove(listener);<a name="line.264"></a>
+<span class="sourceLineNo">265</span> }<a name="line.265"></a>
+<span class="sourceLineNo">266</span><a name="line.266"></a>
+<span class="sourceLineNo">267</span> @Override<a name="line.267"></a>
+<span class="sourceLineNo">268</span> public WALCoprocessorHost getCoprocessorHost() {<a name="line.268"></a>
+<span class="sourceLineNo">269</span> return coprocessorHost;<a name="line.269"></a>
+<span class="sourceLineNo">270</span> }<a name="line.270"></a>
+<span class="sourceLineNo">271</span><a name="line.271"></a>
+<span class="sourceLineNo">272</span> /**<a name="line.272"></a>
+<span class="sourceLineNo">273</span> * FSDataOutputStream associated with the current SequenceFile.writer<a name="line.273"></a>
+<span class="sourceLineNo">274</span> */<a name="line.274"></a>
+<span class="sourceLineNo">275</span> private FSDataOutputStream hdfs_out;<a name="line.275"></a>
+<span class="sourceLineNo">276</span><a name="line.276"></a>
+<span class="sourceLineNo">277</span> // All about log rolling if not enough replicas outstanding.<a name="line.277"></a>
+<span class="sourceLineNo">278</span><a name="line.278"></a>
+<span class="sourceLineNo">279</span> // Minimum tolerable replicas, if the actual value is lower than it, rollWriter will be triggered<a name="line.279"></a>
+<span class="sourceLineNo">280</span> private final int minTolerableReplication;<a name="line.280"></a>
+<span class="sourceLineNo">281</span><a name="line.281"></a>
+<span class="sourceLineNo">282</span> private final int slowSyncNs;<a name="line.282"></a>
+<span class="sourceLineNo">283</span><a name="line.283"></a>
+<span class="sourceLineNo">284</span> // If live datanode count is lower than the default replicas value,<a name="line.284"></a>
+<span class="sourceLineNo">285</span> // RollWriter will be triggered in each sync(So the RollWriter will be<a name="line.285"></a>
+<span class="sourceLineNo">286</span> // triggered one by one in a short time). Using it as a workaround to slow<a name="line.286"></a>
+<span class="sourceLineNo">287</span> // down the roll frequency triggered by checkLowReplication().<a name="line.287"></a>
+<span class="sourceLineNo">288</span> private final AtomicInteger consecutiveLogRolls = new AtomicInteger(0);<a name="line.288"></a>
+<span class="sourceLineNo">289</span><a name="line.289"></a>
+<span class="sourceLineNo">290</span> private final int lowReplicationRollLimit;<a name="line.290"></a>
+<span class="sourceLineNo">291</span><a name="line.291"></a>
+<span class="sourceLineNo">292</span> // If consecutiveLogRolls is larger than lowReplicationRollLimit,<a name="line.292"></a>
+<span class="sourceLineNo">293</span> // then disable the rolling in checkLowReplication().<a name="line.293"></a>
+<span class="sourceLineNo">294</span> // Enable it if the replications recover.<a name="line.294"></a>
+<span class="sourceLineNo">295</span> private volatile boolean lowReplicationRollEnabled = true;<a name="line.295"></a>
+<span class="sourceLineNo">296</span><a name="line.296"></a>
+<span class="sourceLineNo">297</span> /**<a name="line.297"></a>
+<span class="sourceLineNo">298</span> * Class that does accounting of sequenceids in WAL subsystem. Holds oldest outstanding<a name="line.298"></a>
+<span class="sourceLineNo">299</span> * sequence id as yet not flushed as well as the most recent edit sequence id appended to the<a name="line.299"></a>
+<span class="sourceLineNo">300</span> * WAL. Has facility for answering questions such as "Is it safe to GC a WAL?".<a name="line.300"></a>
+<span class="sourceLineNo">301</span> */<a name="line.301"></a>
+<span class="sourceLineNo">302</span> private SequenceIdAccounting sequenceIdAccounting = new SequenceIdAccounting();<a name="line.302"></a>
+<span class="sourceLineNo">303</span><a name="line.303"></a>
+<span class="sourceLineNo">304</span> /**<a name="line.304"></a>
+<span class="sourceLineNo">305</span> * Current log file.<a name="line.305"></a>
+<span class="sourceLineNo">306</span> */<a name="line.306"></a>
+<span class="sourceLineNo">307</span> volatile Writer writer;<a name="line.307"></a>
+<span class="sourceLineNo">308</span><a name="line.308"></a>
+<span class="sourceLineNo">309</span> /** The barrier used to ensure that close() waits for all log rolls and flushes to finish. */<a name="line.309"></a>
+<span class="sourceLineNo">310</span> private final DrainBarrier closeBarrier = new DrainBarrier();<a name="line.310"></a>
+<span class="sourceLineNo">311</span><a name="line.311"></a>
+<span class="sourceLineNo">312</span> /**<a name="line.312"></a>
+<span class="sourceLineNo">313</span> * This lock makes sure only one log roll runs at a time. Should not be taken while any other<a name="line.313"></a>
+<span class="sourceLineNo">314</span> * lock is held. We don't just use synchronized because that results in bogus and tedious<a name="line.314"></a>
+<span class="sourceLineNo">315</span> * findbugs warning when it thinks synchronized controls writer thread safety. It is held when<a name="line.315"></a>
+<span class="sourceLineNo">316</span> * we are actually rolling the log. It is checked when we are looking to see if we should roll<a name="line.316"></a>
+<span class="sourceLineNo">317</span> * the log or not.<a name="line.317"></a>
+<span class="sourceLineNo">318</span> */<a name="line.318"></a>
+<span class="sourceLineNo">319</span> private final ReentrantLock rollWriterLock = new ReentrantLock(true);<a name="line.319"></a>
+<span class="sourceLineNo">320</span><a name="line.320"></a>
+<span class="sourceLineNo">321</span> private volatile boolean closed = false;<a name="line.321"></a>
+<span class="sourceLineNo">322</span> private final AtomicBoolean shutdown = new AtomicBoolean(false);<a name="line.322"></a>
+<span class="sourceLineNo">323</span><a name="line.323"></a>
+<span class="sourceLineNo">324</span> // The timestamp (in ms) when the log file was created.<a name="line.324"></a>
+<span class="sourceLineNo">325</span> private final AtomicLong filenum = new AtomicLong(-1);<a name="line.325"></a>
+<span class="sourceLineNo">326</span><a name="line.326"></a>
+<span class="sourceLineNo">327</span> // Number of transactions in the current Wal.<a name="line.327"></a>
+<span class="sourceLineNo">328</span> private final AtomicInteger numEntries = new AtomicInteger(0);<a name="line.328"></a>
+<span class="sourceLineNo">329</span><a name="line.329"></a>
+<span class="sourceLineNo">330</span> // If > than this size, roll the log.<a name="line.330"></a>
+<span class="sourceLineNo">331</span> private final long logrollsize;<a name="line.331"></a>
+<span class="sourceLineNo">332</span><a name="line.332"></a>
+<span class="sourceLineNo">333</span> /**<a name="line.333"></a>
+<span class="sourceLineNo">334</span> * The total size of wal<a name="line.334"></a>
+<span class="sourceLineNo">335</span> */<a name="line.335"></a>
+<span class="sourceLineNo">336</span> private AtomicLong totalLogSize = new AtomicLong(0);<a name="line.336"></a>
+<span class="sourceLineNo">337</span><a name="line.337"></a>
+<span class="sourceLineNo">338</span> /*<a name="line.338"></a>
+<span class="sourceLineNo">339</span> * If more than this many logs, force flush of oldest region to oldest edit<a name="line.339"></a>
+<span class="sourceLineNo">340</span> * goes to disk. If too many and we crash, then will take forever replaying.<a name="line.340"></a>
+<span class="sourceLineNo">341</span> * Keep the number of logs tidy.<a name="line.341"></a>
+<span class="sourceLineNo">342</span> */<a name="line.342"></a>
+<span class="sourceLineNo">343</span> private final int maxLogs;<a name="line.343"></a>
+<span class="sourceLineNo">344</span><a name="line.344"></a>
+<span class="sourceLineNo">345</span> /** Number of log close errors tolerated before we abort */<a name="line.345"></a>
+<span class="sourceLineNo">346</span> private final int closeErrorsTolerated;<a name="line.346"></a>
+<span class="sourceLineNo">347</span><a name="line.347"></a>
+<span class="sourceLineNo">348</span> private final AtomicInteger closeErrorCount = new AtomicInteger();<a name="line.348"></a>
+<span class="sourceLineNo">349</span><a name="line.349"></a>
<span class="sourceLineNo">350</span><a name="line.350"></a>
-<span class="sourceLineNo">351</span><a name="line.351"></a>
-<span class="sourceLineNo">352</span> /**<a name="line.352"></a>
-<span class="sourceLineNo">353</span> * WAL Comparator; it compares the timestamp (log filenum), present in the log file name.<a name="line.353"></a>
-<span class="sourceLineNo">354</span> * Throws an IllegalArgumentException if used to compare paths from different wals.<a name="line.354"></a>
-<span class="sourceLineNo">355</span> */<a name="line.355"></a>
-<span class="sourceLineNo">356</span> final Comparator<Path> LOG_NAME_COMPARATOR = new Comparator<Path>() {<a name="line.356"></a>
-<span class="sourceLineNo">357</span> @Override<a name="line.357"></a>
-<span class="sourceLineNo">358</span> public int compare(Path o1, Path o2) {<a name="line.358"></a>
-<span class="sourceLineNo">359</span> long t1 = getFileNumFromFileName(o1);<a name="line.359"></a>
-<span class="sourceLineNo">360</span> long t2 = getFileNumFromFileName(o2);<a name="line.360"></a>
-<span class="sourceLineNo">361</span> if (t1 == t2) return 0;<a name="line.361"></a>
-<span class="sourceLineNo">362</span> return (t1 > t2) ? 1 : -1;<a name="line.362"></a>
-<span class="sourceLineNo">363</span> }<a name="line.363"></a>
-<span class="sourceLineNo">364</span> };<a name="line.364"></a>
-<span class="sourceLineNo">365</span><a name="line.365"></a>
-<span class="sourceLineNo">366</span> /**<a name="line.366"></a>
-<span class="sourceLineNo">367</span> * Map of WAL log file to the latest sequence ids of all regions it has entries of.<a name="line.367"></a>
-<span class="sourceLineNo">368</span> * The map is sorted by the log file creation timestamp (contained in the log file name).<a name="line.368"></a>
-<span class="sourceLineNo">369</span> */<a name="line.369"></a>
-<span class="sourceLineNo">370</span> private NavigableMap<Path, Map<byte[], Long>> byWalRegionSequenceIds =<a name="line.370"></a>
-<span class="sourceLineNo">371</span> new ConcurrentSkipListMap<Path, Map<byte[], Long>>(LOG_NAME_COMPARATOR);<a name="line.371"></a>
-<span class="sourceLineNo">372</span><a name="line.372"></a>
-<span class="sourceLineNo">373</span> /**<a name="line.373"></a>
-<span class="sourceLineNo">374</span> * Exception handler to pass the disruptor ringbuffer. Same as native implementation only it<a name="line.374"></a>
-<span class="sourceLineNo">375</span> * logs using our logger instead of java native logger.<a name="line.375"></a>
-<span class="sourceLineNo">376</span> */<a name="line.376"></a>
-<span class="sourceLineNo">377</span> static class RingBufferExceptionHandler implements ExceptionHandler {<a name="line.377"></a>
-<span class="sourceLineNo">378</span> @Override<a name="line.378"></a>
-<span class="sourceLineNo">379</span> public void handleEventException(Throwable ex, long sequence, Object event) {<a name="line.379"></a>
-<span class="sourceLineNo">380</span> LOG.error("Sequence=" + sequence + ", event=" + event, ex);<a name="line.380"></a>
-<span class="sourceLineNo">381</span> throw new RuntimeException(ex);<a name="line.381"></a>
-<span class="sourceLineNo">382</span> }<a name="line.382"></a>
-<span class="sourceLineNo">383</span><a name="line.383"></a>
-<span class="sourceLineNo">384</span> @Override<a name="line.384"></a>
-<span class="sourceLineNo">385</span> public void handleOnStartException(Throwable ex) {<a name="line.385"></a>
-<span class="sourceLineNo">386</span> LOG.error(ex);<a name="line.386"></a>
-<span class="sourceLineNo">387</span> throw new RuntimeException(ex);<a name="line.387"></a>
-<span class="sourceLineNo">388</span> }<a name="line.388"></a>
-<span class="sourceLineNo">389</span><a name="line.389"></a>
-<span class="sourceLineNo">390</span> @Override<a name="line.390"></a>
-<span class="sourceLineNo">391</span> public void handleOnShutdownException(Throwable ex) {<a name="line.391"></a>
-<span class="sourceLineNo">392</span> LOG.error(ex);<a name="line.392"></a>
-<span class="sourceLineNo">393</span> throw new RuntimeException(ex);<a name="line.393"></a>
-<span class="sourceLineNo">394</span> }<a name="line.394"></a>
-<span class="sourceLineNo">395</span> }<a name="line.395"></a>
-<span class="sourceLineNo">396</span><a name="line.396"></a>
-<span class="sourceLineNo">397</span> /**<a name="line.397"></a>
-<span class="sourceLineNo">398</span> * Constructor.<a name="line.398"></a>
-<span class="sourceLineNo">399</span> *<a name="line.399"></a>
-<span class="sourceLineNo">400</span> * @param fs filesystem handle<a name="line.400"></a>
-<span class="sourceLineNo">401</span> * @param root path for stored and archived wals<a name="line.401"></a>
-<span class="sourceLineNo">402</span> * @param logDir dir where wals are stored<a name="line.402"></a>
-<span class="sourceLineNo">403</span> * @param conf configuration to use<a name="line.403"></a>
-<span class="sourceLineNo">404</span> * @throws IOException<a name="line.404"></a>
-<span class="sourceLineNo">405</span> */<a name="line.405"></a>
-<span class="sourceLineNo">406</span> public FSHLog(final FileSystem fs, final Path root, final String logDir, final Configuration conf)<a name="line.406"></a>
-<span class="sourceLineNo">407</span> throws IOException {<a name="line.407"></a>
-<span class="sourceLineNo">408</span> this(fs, root, logDir, HConstants.HREGION_OLDLOGDIR_NAME, conf, null, true, null, null);<a name="line.408"></a>
-<span class="sourceLineNo">409</span> }<a name="line.409"></a>
-<span class="sourceLineNo">410</span><a name="line.410"></a>
-<span class="sourceLineNo">411</span> /**<a name="line.411"></a>
-<span class="sourceLineNo">412</span> * Create an edit log at the given <code>dir</code> location.<a name="line.412"></a>
-<span class="sourceLineNo">413</span> *<a name="line.413"></a>
-<span class="sourceLineNo">414</span> * You should never have to load an existing log. If there is a log at<a name="line.414"></a>
-<span class="sourceLineNo">415</span> * startup, it should have already been processed and deleted by the time the<a name="line.415"></a>
-<span class="sourceLineNo">416</span> * WAL object is started up.<a name="line.416"></a>
-<span class="sourceLineNo">417</span> *<a name="line.417"></a>
-<span class="sourceLineNo">418</span> * @param fs filesystem handle<a name="line.418"></a>
-<span class="sourceLineNo">419</span> * @param rootDir path to where logs and oldlogs<a name="line.419"></a>
-<span class="sourceLineNo">420</span> * @param logDir dir where wals are stored<a name="line.420"></a>
-<span class="sourceLineNo">421</span> * @param archiveDir dir where wals are archived<a name="line.421"></a>
-<span class="sourceLineNo">422</span> * @param conf configuration to use<a name="line.422"></a>
-<span class="sourceLineNo">423</span> * @param listeners Listeners on WAL events. Listeners passed here will<a name="line.423"></a>
-<span class="sourceLineNo">424</span> * be registered before we do anything else; e.g. the<a name="line.424"></a>
-<span class="sourceLineNo">425</span> * Constructor {@link #rollWriter()}.<a name="line.425"></a>
-<span class="sourceLineNo">426</span> * @param failIfWALExists If true IOException will be thrown if files related to this wal<a name="line.426"></a>
-<span class="sourceLineNo">427</span> * already exist.<a name="line.427"></a>
-<span class="sourceLineNo">428</span> * @param prefix should always be hostname and port in distributed env and<a name="line.428"></a>
-<span class="sourceLineNo">429</span> * it will be URL encoded before being used.<a name="line.429"></a>
-<span class="sourceLineNo">430</span> * If prefix is null, "wal" will be used<a name="line.430"></a>
-<span class="sourceLineNo">431</span> * @param suffix will be url encoded. null is treated as empty. non-empty must start with<a name="line.431"></a>
-<span class="sourceLineNo">432</span> * {@link DefaultWALProvider#WAL_FILE_NAME_DELIMITER}<a name="line.432"></a>
-<span class="sourceLineNo">433</span> * @throws IOException<a name="line.433"></a>
-<span class="sourceLineNo">434</span> */<a name="line.434"></a>
-<span class="sourceLineNo">435</span> public FSHLog(final FileSystem fs, final Path rootDir, final String logDir,<a name="line.435"></a>
-<span class="sourceLineNo">436</span> final String archiveDir, final Configuration conf,<a name="line.436"></a>
-<span class="sourceLineNo">437</span> final List<WALActionsListener> listeners,<a name="line.437"></a>
-<span class="sourceLineNo">438</span> final boolean failIfWALExists, final String prefix, final String suffix)<a name="line.438"></a>
-<span class="sourceLineNo">439</span> throws IOException {<a name="line.439"></a>
-<span class="sourceLineNo">440</span> this.fs = fs;<a name="line.440"></a>
-<span class="sourceLineNo">441</span> this.fullPathLogDir = new Path(rootDir, logDir);<a name="line.441"></a>
-<span class="sourceLineNo">442</span> this.fullPathArchiveDir = new Path(rootDir, archiveDir);<a name="line.442"></a>
-<span class="sourceLineNo">443</span> this.conf = conf;<a name="line.443"></a>
-<span class="sourceLineNo">444</span><a name="line.444"></a>
-<span class="sourceLineNo">445</span> if (!fs.exists(fullPathLogDir) && !fs.mkdirs(fullPathLogDir)) {<a name="line.445"></a>
-<span class="sourceLineNo">446</span> throw new IOException("Unable to mkdir " + fullPathLogDir);<a name="line.446"></a>
-<span class="sourceLineNo">447</span> }<a name="line.447"></a>
-<span class="sourceLineNo">448</span><a name="line.448"></a>
-<span class="sourceLineNo">449</span> if (!fs.exists(this.fullPathArchiveDir)) {<a name="line.449"></a>
-<span class="sourceLineNo">450</span> if (!fs.mkdirs(this.fullPathArchiveDir)) {<a name="line.450"></a>
-<span class="sourceLineNo">451</span> throw new IOException("Unable to mkdir " + this.fullPathArchiveDir);<a name="line.451"></a>
-<span class="sourceLineNo">452</span> }<a name="line.452"></a>
-<span class="sourceLineNo">453</span> }<a name="line.453"></a>
-<span class="sourceLineNo">454</span><a name="line.454"></a>
-<span class="sourceLineNo">455</span> // If prefix is null||empty then just name it wal<a name="line.455"></a>
-<span class="sourceLineNo">456</span> this.logFilePrefix =<a name="line.456"></a>
-<span class="sourceLineNo">457</span> prefix == null || prefix.isEmpty() ? "wal" : URLEncoder.encode(prefix, "UTF8");<a name="line.457"></a>
-<span class="sourceLineNo">458</span> // we only correctly differentiate suffices when numeric ones start with '.'<a name="line.458"></a>
-<span class="sourceLineNo">459</span> if (suffix != null && !(suffix.isEmpty()) && !(suffix.startsWith(WAL_FILE_NAME_DELIMITER))) {<a name="line.459"></a>
-<span class="sourceLineNo">460</span> throw new IllegalArgumentException("WAL suffix must start with '" + WAL_FILE_NAME_DELIMITER +<a name="line.460"></a>
-<span class="sourceLineNo">461</span> "' but instead was '" + suffix + "'");<a name="line.461"></a>
-<span class="sourceLineNo">462</span> }<a name="line.462"></a>
-<span class="sourceLineNo">463</span> // Now that it exists, set the storage policy for the entire directory of wal files related to<a name="line.463"></a>
-<span class="sourceLineNo">464</span> // this FSHLog instance<a name="line.464"></a>
-<span class="sourceLineNo">465</span> FSUtils.setStoragePolicy(fs, conf, this.fullPathLogDir, HConstants.WAL_STORAGE_POLICY,<a name="line.465"></a>
-<span class="sourceLineNo">466</span> HConstants.DEFAULT_WAL_STORAGE_POLICY);<a name="line.466"></a>
-<span class="sourceLineNo">467</span> this.logFileSuffix = (suffix == null) ? "" : URLEncoder.encode(suffix, "UTF8");<a name="line.467"></a>
-<span class="sourceLineNo">468</span> this.prefixPathStr = new Path(fullPathLogDir,<a name="line.468"></a>
-<span class="sourceLineNo">469</span> logFilePrefix + WAL_FILE_NAME_DELIMITER).toString();<a name="line.469"></a>
-<span class="sourceLineNo">470</span><a name="line.470"></a>
-<span class="sourceLineNo">471</span> this.ourFiles = new PathFilter() {<a name="line.471"></a>
-<span class="sourceLineNo">472</span> @Override<a name="line.472"></a>
-<span class="sourceLineNo">473</span> public boolean accept(final Path fileName) {<a name="line.473"></a>
-<span class="sourceLineNo">474</span> // The path should start with dir/<prefix> and end with our suffix<a name="line.474"></a>
-<span class="sourceLineNo">475</span> final String fileNameString = fileName.toString();<a name="line.475"></a>
-<span class="sourceLineNo">476</span> if (!fileNameString.startsWith(prefixPathStr)) {<a name="line.476"></a>
-<span class="sourceLineNo">477</span> return false;<a name="line.477"></a>
-<span class="sourceLineNo">478</span> }<a name="line.478"></a>
-<span class="sourceLineNo">479</span> if (logFileSuffix.isEmpty()) {<a name="line.479"></a>
-<span class="sourceLineNo">480</span> // in the case of the null suffix, we need to ensure the filename ends with a timestamp.<a name="line.480"></a>
-<span class="sourceLineNo">481</span> return org.apache.commons.lang.StringUtils.isNumeric(<a name="line.481"></a>
-<span class="sourceLineNo">482</span> fileNameString.substring(prefixPathStr.length()));<a name="line.482"></a>
-<span class="sourceLineNo">483</span> } else if (!fileNameString.endsWith(logFileSuffix)) {<a name="line.483"></a>
-<span class="sourceLineNo">484</span> return false;<a name="line.484"></a>
-<span class="sourceLineNo">485</span> }<a name="line.485"></a>
-<span class="sourceLineNo">486</span> return true;<a name="line.486"></a>
-<span class="sourceLineNo">487</span> }<a name="line.487"></a>
-<span class="sourceLineNo">488</span> };<a name="line.488"></a>
-<span class="sourceLineNo">489</span><a name="line.489"></a>
-<span class="sourceLineNo">490</span> if (failIfWALExists) {<a name="line.490"></a>
-<span class="sourceLineNo">491</span> final FileStatus[] walFiles = FSUtils.listStatus(fs, fullPathLogDir, ourFiles);<a name="line.491"></a>
-<span class="sourceLineNo">492</span> if (null != walFiles && 0 != walFiles.length) {<a name="line.492"></a>
-<span class="sourceLineNo">493</span> throw new IOException("Target WAL already exists within directory " + fullPathLogDir);<a name="line.493"></a>
-<span class="sourceLineNo">494</span> }<a name="line.494"></a>
-<span class="sourceLineNo">495</span> }<a name="line.495"></a>
-<span class="sourceLineNo">496</span><a name="line.496"></a>
-<span class="sourceLineNo">497</span> // Register listeners. TODO: Should this exist anymore? We have CPs?<a name="line.497"></a>
-<span class="sourceLineNo">498</span> if (listeners != null) {<a name="line.498"></a>
-<span class="sourceLineNo">499</span> for (WALActionsListener i: listeners) {<a name="line.499"></a>
-<span class="sourceLineNo">500</span> registerWALActionsListener(i);<a name="line.500"></a>
-<span class="sourceLineNo">501</span> }<a name="line.501"></a>
-<span class="sourceLineNo">502</span> }<a name="line.502"></a>
-<span class="sourceLineNo">503</span> this.coprocessorHost = new WALCoprocessorHost(this, conf);<a name="line.503"></a>
-<span class="sourceLineNo">504</span><a name="line.504"></a>
-<span class="sourceLineNo">505</span> // Get size to roll log at. Roll at 95% of HDFS block size so we avoid crossing HDFS blocks<a name="line.505"></a>
-<span class="sourceLineNo">506</span> // (it costs a little x'ing bocks)<a name="line.506"></a>
-<span class="sourceLineNo">507</span> final long blocksize = this.conf.getLong("hbase.regionserver.hlog.blocksize",<a name="line.507"></a>
-<span class="sourceLineNo">508</span> FSUtils.getDefaultBlockSize(this.fs, this.fullPathLogDir));<a name="line.508"></a>
-<span class="sourceLineNo">509</span> this.logrollsize =<a name="line.509"></a>
-<span class="sourceLineNo">510</span> (long)(blocksize * conf.getFloat("hbase.regionserver.logroll.multiplier", 0.95f));<a name="line.510"></a>
-<span class="sourceLineNo">511</span> <a name="line.511"></a>
-<span class="sourceLineNo">512</span> float memstoreRatio = conf.getFloat(HeapMemorySizeUti
<TRUNCATED>