http://git-wip-us.apache.org/repos/asf/hbase-site/blob/1241ee85/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
----------------------------------------------------------------------
diff --git 
a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
 
b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
index 573de43..4e9c7c3 100644
--- 
a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
+++ 
b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
@@ -32,1012 +32,1081 @@
 <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.util.ArrayList;<a 
name="line.26"></a>
-<span class="sourceLineNo">027</span>import java.util.List;<a 
name="line.27"></a>
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name="line.28"></a>
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java.util.concurrent.CountDownLatch;<a name="line.29"></a>
-<span class="sourceLineNo">030</span>import 
java.util.concurrent.locks.ReentrantLock;<a name="line.30"></a>
-<span class="sourceLineNo">031</span><a name="line.31"></a>
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name="line.32"></a>
-<span class="sourceLineNo">033</span>import 
org.apache.commons.logging.LogFactory;<a name="line.33"></a>
-<span class="sourceLineNo">034</span>import org.apache.hadoop.hbase.Cell;<a 
name="line.34"></a>
-<span class="sourceLineNo">035</span>import 
org.apache.hadoop.hbase.CellComparator;<a name="line.35"></a>
-<span class="sourceLineNo">036</span>import 
org.apache.hadoop.hbase.CellUtil;<a name="line.36"></a>
-<span class="sourceLineNo">037</span>import 
org.apache.hadoop.hbase.DoNotRetryIOException;<a name="line.37"></a>
-<span class="sourceLineNo">038</span>import 
org.apache.hadoop.hbase.HConstants;<a name="line.38"></a>
-<span class="sourceLineNo">039</span>import 
org.apache.hadoop.hbase.KeyValue;<a name="line.39"></a>
-<span class="sourceLineNo">040</span>import 
org.apache.hadoop.hbase.KeyValueUtil;<a name="line.40"></a>
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org.apache.hadoop.hbase.classification.InterfaceAudience;<a name="line.41"></a>
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org.apache.hadoop.hbase.client.IsolationLevel;<a name="line.42"></a>
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org.apache.hadoop.hbase.client.Scan;<a name="line.43"></a>
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org.apache.hadoop.hbase.executor.ExecutorService;<a name="line.44"></a>
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org.apache.hadoop.hbase.filter.Filter;<a name="line.45"></a>
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org.apache.hadoop.hbase.regionserver.ScannerContext.LimitScope;<a 
name="line.46"></a>
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org.apache.hadoop.hbase.regionserver.ScannerContext.NextState;<a 
name="line.47"></a>
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org.apache.hadoop.hbase.regionserver.handler.ParallelSeekHandler;<a 
name="line.48"></a>
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org.apache.hadoop.hbase.regionserver.querymatcher.CompactionScanQueryMatcher;<a 
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org.apache.hadoop.hbase.regionserver.querymatcher.LegacyScanQueryMatcher;<a 
name="line.50"></a>
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org.apache.hadoop.hbase.regionserver.querymatcher.ScanQueryMatcher;<a 
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-<span class="sourceLineNo">052</span>import 
org.apache.hadoop.hbase.regionserver.querymatcher.UserScanQueryMatcher;<a 
name="line.52"></a>
-<span class="sourceLineNo">053</span>import 
org.apache.hadoop.hbase.util.EnvironmentEdgeManager;<a name="line.53"></a>
-<span class="sourceLineNo">054</span><a name="line.54"></a>
-<span class="sourceLineNo">055</span>/**<a name="line.55"></a>
-<span class="sourceLineNo">056</span> * Scanner scans both the memstore and 
the Store. Coalesce KeyValue stream<a name="line.56"></a>
-<span class="sourceLineNo">057</span> * into List&amp;lt;KeyValue&amp;gt; for 
a single row.<a name="line.57"></a>
-<span class="sourceLineNo">058</span> */<a name="line.58"></a>
-<span class="sourceLineNo">059</span>@InterfaceAudience.Private<a 
name="line.59"></a>
-<span class="sourceLineNo">060</span>public class StoreScanner extends 
NonReversedNonLazyKeyValueScanner<a name="line.60"></a>
-<span class="sourceLineNo">061</span>    implements KeyValueScanner, 
InternalScanner, ChangedReadersObserver {<a name="line.61"></a>
-<span class="sourceLineNo">062</span>  private static final Log LOG = 
LogFactory.getLog(StoreScanner.class);<a name="line.62"></a>
-<span class="sourceLineNo">063</span>  // In unit tests, the store could be 
null<a name="line.63"></a>
-<span class="sourceLineNo">064</span>  protected final Store store;<a 
name="line.64"></a>
-<span class="sourceLineNo">065</span>  protected ScanQueryMatcher matcher;<a 
name="line.65"></a>
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name="line.66"></a>
-<span class="sourceLineNo">067</span>  protected boolean cacheBlocks;<a 
name="line.67"></a>
-<span class="sourceLineNo">068</span><a name="line.68"></a>
-<span class="sourceLineNo">069</span>  protected long countPerRow = 0;<a 
name="line.69"></a>
-<span class="sourceLineNo">070</span>  protected int storeLimit = -1;<a 
name="line.70"></a>
-<span class="sourceLineNo">071</span>  protected int storeOffset = 0;<a 
name="line.71"></a>
-<span class="sourceLineNo">072</span><a name="line.72"></a>
-<span class="sourceLineNo">073</span>  // Used to indicate that the scanner 
has closed (see HBASE-1107)<a name="line.73"></a>
-<span class="sourceLineNo">074</span>  // Doesnt need to be volatile because 
it's always accessed via synchronized methods<a name="line.74"></a>
-<span class="sourceLineNo">075</span>  protected boolean closing = false;<a 
name="line.75"></a>
-<span class="sourceLineNo">076</span>  protected final boolean get;<a 
name="line.76"></a>
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explicitColumnQuery;<a name="line.77"></a>
-<span class="sourceLineNo">078</span>  protected final boolean 
useRowColBloom;<a name="line.78"></a>
-<span class="sourceLineNo">079</span>  /**<a name="line.79"></a>
-<span class="sourceLineNo">080</span>   * A flag that enables StoreFileScanner 
parallel-seeking<a name="line.80"></a>
-<span class="sourceLineNo">081</span>   */<a name="line.81"></a>
-<span class="sourceLineNo">082</span>  protected boolean parallelSeekEnabled = 
false;<a name="line.82"></a>
-<span class="sourceLineNo">083</span>  protected ExecutorService executor;<a 
name="line.83"></a>
-<span class="sourceLineNo">084</span>  protected final Scan scan;<a 
name="line.84"></a>
-<span class="sourceLineNo">085</span>  protected final 
NavigableSet&lt;byte[]&gt; columns;<a name="line.85"></a>
-<span class="sourceLineNo">086</span>  protected final long 
oldestUnexpiredTS;<a name="line.86"></a>
-<span class="sourceLineNo">087</span>  protected final long now;<a 
name="line.87"></a>
-<span class="sourceLineNo">088</span>  protected final int minVersions;<a 
name="line.88"></a>
-<span class="sourceLineNo">089</span>  protected final long maxRowSize;<a 
name="line.89"></a>
-<span class="sourceLineNo">090</span>  protected final long 
cellsPerHeartbeatCheck;<a name="line.90"></a>
-<span class="sourceLineNo">091</span><a name="line.91"></a>
-<span class="sourceLineNo">092</span>  // Collects all the KVHeap that are 
eagerly getting closed during the<a name="line.92"></a>
-<span class="sourceLineNo">093</span>  // course of a scan<a 
name="line.93"></a>
-<span class="sourceLineNo">094</span>  protected List&lt;KeyValueHeap&gt; 
heapsForDelayedClose = new ArrayList&lt;&gt;();<a name="line.94"></a>
-<span class="sourceLineNo">095</span><a name="line.95"></a>
-<span class="sourceLineNo">096</span>  /**<a name="line.96"></a>
-<span class="sourceLineNo">097</span>   * The number of KVs seen by the 
scanner. Includes explicitly skipped KVs, but not<a name="line.97"></a>
-<span class="sourceLineNo">098</span>   * KVs skipped via seeking to next 
row/column. TODO: estimate them?<a name="line.98"></a>
-<span class="sourceLineNo">099</span>   */<a name="line.99"></a>
-<span class="sourceLineNo">100</span>  private long kvsScanned = 0;<a 
name="line.100"></a>
-<span class="sourceLineNo">101</span>  private Cell prevCell = null;<a 
name="line.101"></a>
-<span class="sourceLineNo">102</span><a name="line.102"></a>
-<span class="sourceLineNo">103</span>  /** We don't ever expect to change 
this, the constant is just for clarity. */<a name="line.103"></a>
-<span class="sourceLineNo">104</span>  static final boolean 
LAZY_SEEK_ENABLED_BY_DEFAULT = true;<a name="line.104"></a>
-<span class="sourceLineNo">105</span>  public static final String 
STORESCANNER_PARALLEL_SEEK_ENABLE =<a name="line.105"></a>
-<span class="sourceLineNo">106</span>      
"hbase.storescanner.parallel.seek.enable";<a name="line.106"></a>
+<span class="sourceLineNo">027</span>import java.util.HashMap;<a 
name="line.27"></a>
+<span class="sourceLineNo">028</span>import java.util.List;<a 
name="line.28"></a>
+<span class="sourceLineNo">029</span>import java.util.Map;<a 
name="line.29"></a>
+<span class="sourceLineNo">030</span>import java.util.NavigableSet;<a 
name="line.30"></a>
+<span class="sourceLineNo">031</span>import 
java.util.concurrent.CountDownLatch;<a name="line.31"></a>
+<span class="sourceLineNo">032</span>import 
java.util.concurrent.locks.ReentrantLock;<a name="line.32"></a>
+<span class="sourceLineNo">033</span><a name="line.33"></a>
+<span class="sourceLineNo">034</span>import org.apache.commons.logging.Log;<a 
name="line.34"></a>
+<span class="sourceLineNo">035</span>import 
org.apache.commons.logging.LogFactory;<a name="line.35"></a>
+<span class="sourceLineNo">036</span>import org.apache.hadoop.hbase.Cell;<a 
name="line.36"></a>
+<span class="sourceLineNo">037</span>import 
org.apache.hadoop.hbase.CellComparator;<a name="line.37"></a>
+<span class="sourceLineNo">038</span>import 
org.apache.hadoop.hbase.CellUtil;<a name="line.38"></a>
+<span class="sourceLineNo">039</span>import 
org.apache.hadoop.hbase.DoNotRetryIOException;<a name="line.39"></a>
+<span class="sourceLineNo">040</span>import 
org.apache.hadoop.hbase.HConstants;<a name="line.40"></a>
+<span class="sourceLineNo">041</span>import 
org.apache.hadoop.hbase.KeyValue;<a name="line.41"></a>
+<span class="sourceLineNo">042</span>import 
org.apache.hadoop.hbase.KeyValueUtil;<a name="line.42"></a>
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org.apache.hadoop.hbase.classification.InterfaceAudience;<a name="line.43"></a>
+<span class="sourceLineNo">044</span>import 
org.apache.hadoop.hbase.client.IsolationLevel;<a name="line.44"></a>
+<span class="sourceLineNo">045</span>import 
org.apache.hadoop.hbase.client.Scan;<a name="line.45"></a>
+<span class="sourceLineNo">046</span>import 
org.apache.hadoop.hbase.executor.ExecutorService;<a name="line.46"></a>
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org.apache.hadoop.hbase.filter.Filter;<a name="line.47"></a>
+<span class="sourceLineNo">048</span>import 
org.apache.hadoop.hbase.regionserver.ScannerContext.LimitScope;<a 
name="line.48"></a>
+<span class="sourceLineNo">049</span>import 
org.apache.hadoop.hbase.regionserver.ScannerContext.NextState;<a 
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org.apache.hadoop.hbase.regionserver.handler.ParallelSeekHandler;<a 
name="line.50"></a>
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org.apache.hadoop.hbase.regionserver.querymatcher.CompactionScanQueryMatcher;<a 
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org.apache.hadoop.hbase.regionserver.querymatcher.LegacyScanQueryMatcher;<a 
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org.apache.hadoop.hbase.regionserver.querymatcher.ScanQueryMatcher;<a 
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org.apache.hadoop.hbase.regionserver.querymatcher.UserScanQueryMatcher;<a 
name="line.54"></a>
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org.apache.hadoop.hbase.util.EnvironmentEdgeManager;<a name="line.55"></a>
+<span class="sourceLineNo">056</span><a name="line.56"></a>
+<span class="sourceLineNo">057</span>/**<a name="line.57"></a>
+<span class="sourceLineNo">058</span> * Scanner scans both the memstore and 
the Store. Coalesce KeyValue stream into List&amp;lt;KeyValue&amp;gt;<a 
name="line.58"></a>
+<span class="sourceLineNo">059</span> * for a single row.<a name="line.59"></a>
+<span class="sourceLineNo">060</span> * &lt;p&gt;<a name="line.60"></a>
+<span class="sourceLineNo">061</span> * The implementation is not thread safe. 
So there will be no race between next and close. The only<a name="line.61"></a>
+<span class="sourceLineNo">062</span> * exception is updateReaders, it will be 
called in the memstore flush thread to indicate that there<a name="line.62"></a>
+<span class="sourceLineNo">063</span> * is a flush.<a name="line.63"></a>
+<span class="sourceLineNo">064</span> */<a name="line.64"></a>
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name="line.65"></a>
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NonReversedNonLazyKeyValueScanner<a name="line.66"></a>
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InternalScanner, ChangedReadersObserver {<a name="line.67"></a>
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LogFactory.getLog(StoreScanner.class);<a name="line.68"></a>
+<span class="sourceLineNo">069</span>  // In unit tests, the store could be 
null<a name="line.69"></a>
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it's always accessed via synchronized methods<a name="line.80"></a>
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explicitColumnQuery;<a name="line.83"></a>
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name="line.84"></a>
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+<span class="sourceLineNo">086</span>   * A flag that enables StoreFileScanner 
parallel-seeking<a name="line.86"></a>
+<span class="sourceLineNo">087</span>   */<a name="line.87"></a>
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false;<a name="line.88"></a>
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name="line.91"></a>
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name="line.92"></a>
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name="line.93"></a>
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name="line.94"></a>
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cellsPerHeartbeatCheck;<a name="line.95"></a>
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+<span class="sourceLineNo">097</span>  // Collects all the KVHeap that are 
eagerly getting closed during the<a name="line.97"></a>
+<span class="sourceLineNo">098</span>  // course of a scan<a 
name="line.98"></a>
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heapsForDelayedClose = new ArrayList&lt;&gt;();<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>   * The number of KVs seen by the 
scanner. Includes explicitly skipped KVs, but not<a name="line.102"></a>
+<span class="sourceLineNo">103</span>   * KVs skipped via seeking to next 
row/column. TODO: estimate them?<a name="line.103"></a>
+<span class="sourceLineNo">104</span>   */<a name="line.104"></a>
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name="line.105"></a>
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name="line.106"></a>
 <span class="sourceLineNo">107</span><a name="line.107"></a>
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name="line.110"></a>
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between timeout checks. Specifying a larger value means that<a 
name="line.113"></a>
-<span class="sourceLineNo">114</span>   * timeout checks will occur less 
frequently. Specifying a small value will lead to more frequent<a 
name="line.114"></a>
-<span class="sourceLineNo">115</span>   * timeout checks.<a 
name="line.115"></a>
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HBASE_CELLS_SCANNED_PER_HEARTBEAT_CHECK =<a name="line.117"></a>
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"hbase.cells.scanned.per.heartbeat.check";<a name="line.118"></a>
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#HBASE_CELLS_SCANNED_PER_HEARTBEAT_CHECK}.<a name="line.121"></a>
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DEFAULT_HBASE_CELLS_SCANNED_PER_HEARTBEAT_CHECK = 10000;<a name="line.123"></a>
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you need to reseek given the key below<a name="line.125"></a>
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name="line.126"></a>
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name="line.128"></a>
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name="line.129"></a>
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during the course of the scan<a name="line.130"></a>
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false;<a name="line.131"></a>
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flush<a name="line.132"></a>
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flushedStoreFiles = new ArrayList&lt;&gt;(1);<a name="line.133"></a>
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name="line.134"></a>
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currentScanners = new ArrayList&lt;&gt;();<a name="line.135"></a>
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name="line.136"></a>
-<span class="sourceLineNo">137</span>  private ReentrantLock flushLock = new 
ReentrantLock();<a name="line.137"></a>
+<span class="sourceLineNo">108</span>  private final long preadMaxBytes;<a 
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name="line.109"></a>
+<span class="sourceLineNo">110</span><a name="line.110"></a>
+<span class="sourceLineNo">111</span>  /** We don't ever expect to change 
this, the constant is just for clarity. */<a name="line.111"></a>
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LAZY_SEEK_ENABLED_BY_DEFAULT = true;<a name="line.112"></a>
+<span class="sourceLineNo">113</span>  public static final String 
STORESCANNER_PARALLEL_SEEK_ENABLE =<a name="line.113"></a>
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"hbase.storescanner.parallel.seek.enable";<a name="line.114"></a>
+<span class="sourceLineNo">115</span><a name="line.115"></a>
+<span class="sourceLineNo">116</span>  /** Used during unit testing to ensure 
that lazy seek does save seek ops */<a name="line.116"></a>
+<span class="sourceLineNo">117</span>  private static boolean 
lazySeekEnabledGlobally = LAZY_SEEK_ENABLED_BY_DEFAULT;<a name="line.117"></a>
+<span class="sourceLineNo">118</span><a name="line.118"></a>
+<span class="sourceLineNo">119</span>  /**<a name="line.119"></a>
+<span class="sourceLineNo">120</span>   * The number of cells scanned in 
between timeout checks. Specifying a larger value means that<a 
name="line.120"></a>
+<span class="sourceLineNo">121</span>   * timeout checks will occur less 
frequently. Specifying a small value will lead to more frequent<a 
name="line.121"></a>
+<span class="sourceLineNo">122</span>   * timeout checks.<a 
name="line.122"></a>
+<span class="sourceLineNo">123</span>   */<a name="line.123"></a>
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HBASE_CELLS_SCANNED_PER_HEARTBEAT_CHECK =<a name="line.124"></a>
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matcher.getStartKey(), explicitColumnQuery &amp;&amp; 
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earliestPutTs) throws IOException {<a name="line.260"></a>
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smallestReadPoint,<a name="line.292"></a>
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now, dropDeletesFromRow, dropDeletesToRow,<a name="line.297"></a>
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oldestUnexpiredTS, now, null, null, store.getCoprocessorHost());<a 
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false;<a name="line.145"></a>
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flush<a name="line.146"></a>
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name="line.148"></a>
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name="line.150"></a>
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test race between StoreScanner construction and compaction<a 
name="line.155"></a>
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name="line.156"></a>
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columns, long readPt, boolean cacheBlocks) {<a name="line.164"></a>
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scanInfo.getMinVersions();<a name="line.174"></a>
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because this is not done in<a name="line.178"></a>
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user specific stream. Will change to stream later if<a name="line.192"></a>
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keeps running for a long time.<a name="line.193"></a>
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scanInfo.getCellsPerTimeoutCheck();<a name="line.197"></a>
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config allows and more there is more than one store file.<a name="line.198"></a>
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this.store.getStorefilesCount() &gt; 1) {<a name="line.199"></a>
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true;<a name="line.202"></a>
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addCurrentScanners(List&lt;? extends KeyValueScanner&gt; scanners) {<a 
name="line.208"></a>
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this.currentScanners.addAll(scanners);<a name="line.209"></a>
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snapshot, and all StoreFiles. Assumes we<a name="line.213"></a>
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name="line.214"></a>
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name="line.216"></a>
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name="line.217"></a>
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scanning<a name="line.218"></a>
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name="line.219"></a>
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ScanInfo scanInfo, Scan scan, final NavigableSet&lt;byte[]&gt; columns,<a 
name="line.221"></a>
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name="line.223"></a>
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readPt, scan.getCacheBlocks());<a name="line.224"></a>
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scan.isRaw()) {<a name="line.225"></a>
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DoNotRetryIOException("Cannot specify any column for a raw scan");<a 
name="line.226"></a>
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UserScanQueryMatcher.create(scan, scanInfo, columns, oldestUnexpiredTS, now,<a 
name="line.228"></a>
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name="line.229"></a>
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this.store.addChangedReaderObserver(this);<a name="line.231"></a>
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out unnecessary StoreFiles.<a name="line.234"></a>
+<span class="sourceLineNo">235</span>      List&lt;KeyValueScanner&gt; 
scanners = getScannersNoCompaction();<a name="line.235"></a>
+<span class="sourceLineNo">236</span><a name="line.236"></a>
+<span class="sourceLineNo">237</span>      // Seek all scanners to the start 
of the Row (or if the exact matching row<a name="line.237"></a>
+<span class="sourceLineNo">238</span>      // key does not exist, then to the 
start of the next matching Row).<a name="line.238"></a>
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optimize the top row seek for delete<a name="line.239"></a>
+<span class="sourceLineNo">240</span>      // family marker.<a 
name="line.240"></a>
+<span class="sourceLineNo">241</span>      seekScanners(scanners, 
matcher.getStartKey(), explicitColumnQuery &amp;&amp; 
lazySeekEnabledGlobally,<a name="line.241"></a>
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name="line.242"></a>
+<span class="sourceLineNo">243</span><a name="line.243"></a>
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name="line.244"></a>
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scan.getMaxResultsPerColumnFamily();<a name="line.245"></a>
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readPoint that we should use for tracking versions<a name="line.283"></a>
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inclusive left bound of the range; can be EMPTY_START_ROW.<a 
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exclusive right bound of the range; can be EMPTY_END_ROW.<a name="line.285"></a>
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smallestReadPoint,<a name="line.304"></a>
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now, dropDeletesFromRow, dropDeletesToRow,<a name="line.309"></a>
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name="line.310"></a>
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store.getComparator());<a name="line.320"></a>
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columns, final List&lt;? extends KeyValueScanner&gt; scanners, long 
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!scan.getTimeRange().isAllTime() || columns != null) {<a name="line.354"></a>
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scan.getStopRow(), scan.includeStopRow(), this.readPt));<a name="line.378"></a>
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parallel seek<a name="line.386"></a>
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name="line.387"></a>
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boolean isParallelSeek)<a name="line.390"></a>
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name="line.391"></a>
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the Row (or if the exact matching row<a name="line.392"></a>
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start of the next matching Row).<a name="line.393"></a>
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optimize the top row seek for delete<a name="line.394"></a>
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comparator);<a name="line.423"></a>
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selectScannersFrom(<a name="line.433"></a>
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based on TTL if minVersions is set to 0.<a name="line.448"></a>
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KVs that have technically expired.<a name="line.449"></a>
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minVersions == 0 ? oldestUnexpiredTS: Long.MIN_VALUE;<a name="line.450"></a>
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-<span class="sourceLineNo">463</span>    throw new RuntimeException("Never 
call StoreScanner.next()");<a name="line.463"></a>
-<span class="sourceLineNo">464</span>  }<a name="line.464"></a>
-<span class="sourc

<TRUNCATED>

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