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From git-site-r...@apache.org
Subject [14/51] [partial] hbase-site git commit: Published site at .
Date Thu, 17 Aug 2017 15:07:24 GMT
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/33bc9e06/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.FavoredNodeLocalityPicker.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.FavoredNodeLocalityPicker.html b/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.FavoredNodeLocalityPicker.html
index b5f351a..de70e5b 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.FavoredNodeLocalityPicker.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/FavoredStochasticBalancer.FavoredNodeLocalityPicker.html
@@ -51,700 +51,703 @@
 <span class="sourceLineNo">043</span>import org.apache.hadoop.hbase.favored.FavoredNodesPlan;<a name="line.43"></a>
 <span class="sourceLineNo">044</span>import org.apache.hadoop.hbase.favored.FavoredNodesPlan.Position;<a name="line.44"></a>
 <span class="sourceLineNo">045</span>import org.apache.hadoop.hbase.favored.FavoredNodesPromoter;<a name="line.45"></a>
-<span class="sourceLineNo">046</span>import org.apache.hadoop.hbase.master.MasterServices;<a name="line.46"></a>
-<span class="sourceLineNo">047</span>import org.apache.hadoop.hbase.master.RegionPlan;<a name="line.47"></a>
-<span class="sourceLineNo">048</span>import org.apache.hadoop.hbase.util.Pair;<a name="line.48"></a>
-<span class="sourceLineNo">049</span><a name="line.49"></a>
-<span class="sourceLineNo">050</span>import org.apache.hadoop.hbase.shaded.com.google.common.collect.Lists;<a name="line.50"></a>
-<span class="sourceLineNo">051</span>import org.apache.hadoop.hbase.shaded.com.google.common.collect.Maps;<a name="line.51"></a>
-<span class="sourceLineNo">052</span>import org.apache.hadoop.hbase.shaded.com.google.common.collect.Sets;<a name="line.52"></a>
-<span class="sourceLineNo">053</span><a name="line.53"></a>
-<span class="sourceLineNo">054</span>/**<a name="line.54"></a>
-<span class="sourceLineNo">055</span> * An implementation of the {@link org.apache.hadoop.hbase.master.LoadBalancer} that<a name="line.55"></a>
-<span class="sourceLineNo">056</span> * assigns favored nodes for each region. There is a Primary RegionServer that hosts<a name="line.56"></a>
-<span class="sourceLineNo">057</span> * the region, and then there is Secondary and Tertiary RegionServers. Currently, the<a name="line.57"></a>
-<span class="sourceLineNo">058</span> * favored nodes information is used in creating HDFS files - the Primary RegionServer<a name="line.58"></a>
-<span class="sourceLineNo">059</span> * passes the primary, secondary, tertiary node addresses as hints to the<a name="line.59"></a>
-<span class="sourceLineNo">060</span> * DistributedFileSystem API for creating files on the filesystem. These nodes are<a name="line.60"></a>
-<span class="sourceLineNo">061</span> * treated as hints by the HDFS to place the blocks of the file. This alleviates the<a name="line.61"></a>
-<span class="sourceLineNo">062</span> * problem to do with reading from remote nodes (since we can make the Secondary<a name="line.62"></a>
-<span class="sourceLineNo">063</span> * RegionServer as the new Primary RegionServer) after a region is recovered. This<a name="line.63"></a>
-<span class="sourceLineNo">064</span> * should help provide consistent read latencies for the regions even when their<a name="line.64"></a>
-<span class="sourceLineNo">065</span> * primary region servers die. This provides two<a name="line.65"></a>
-<span class="sourceLineNo">066</span> * {@link org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer.CandidateGenerator}<a name="line.66"></a>
-<span class="sourceLineNo">067</span> *<a name="line.67"></a>
-<span class="sourceLineNo">068</span> */<a name="line.68"></a>
-<span class="sourceLineNo">069</span>public class FavoredStochasticBalancer extends StochasticLoadBalancer implements<a name="line.69"></a>
-<span class="sourceLineNo">070</span>    FavoredNodesPromoter {<a name="line.70"></a>
-<span class="sourceLineNo">071</span><a name="line.71"></a>
-<span class="sourceLineNo">072</span>  private static final Log LOG = LogFactory.getLog(FavoredStochasticBalancer.class);<a name="line.72"></a>
-<span class="sourceLineNo">073</span>  private FavoredNodesManager fnm;<a name="line.73"></a>
-<span class="sourceLineNo">074</span><a name="line.74"></a>
-<span class="sourceLineNo">075</span>  @Override<a name="line.75"></a>
-<span class="sourceLineNo">076</span>  public void initialize() throws HBaseIOException {<a name="line.76"></a>
-<span class="sourceLineNo">077</span>    configureGenerators();<a name="line.77"></a>
-<span class="sourceLineNo">078</span>    super.initialize();<a name="line.78"></a>
-<span class="sourceLineNo">079</span>  }<a name="line.79"></a>
-<span class="sourceLineNo">080</span><a name="line.80"></a>
-<span class="sourceLineNo">081</span>  protected void configureGenerators() {<a name="line.81"></a>
-<span class="sourceLineNo">082</span>    List&lt;CandidateGenerator&gt; fnPickers = new ArrayList&lt;&gt;(2);<a name="line.82"></a>
-<span class="sourceLineNo">083</span>    fnPickers.add(new FavoredNodeLoadPicker());<a name="line.83"></a>
-<span class="sourceLineNo">084</span>    fnPickers.add(new FavoredNodeLocalityPicker());<a name="line.84"></a>
-<span class="sourceLineNo">085</span>    setCandidateGenerators(fnPickers);<a name="line.85"></a>
-<span class="sourceLineNo">086</span>  }<a name="line.86"></a>
-<span class="sourceLineNo">087</span><a name="line.87"></a>
-<span class="sourceLineNo">088</span>  @Override<a name="line.88"></a>
-<span class="sourceLineNo">089</span>  public void setMasterServices(MasterServices masterServices) {<a name="line.89"></a>
-<span class="sourceLineNo">090</span>    super.setMasterServices(masterServices);<a name="line.90"></a>
-<span class="sourceLineNo">091</span>    fnm = masterServices.getFavoredNodesManager();<a name="line.91"></a>
-<span class="sourceLineNo">092</span>  }<a name="line.92"></a>
-<span class="sourceLineNo">093</span><a name="line.93"></a>
-<span class="sourceLineNo">094</span>  /*<a name="line.94"></a>
-<span class="sourceLineNo">095</span>   * Round robin assignment: Segregate the regions into two types:<a name="line.95"></a>
-<span class="sourceLineNo">096</span>   *<a name="line.96"></a>
-<span class="sourceLineNo">097</span>   * 1. The regions that have favored node assignment where at least one of the favored node<a name="line.97"></a>
-<span class="sourceLineNo">098</span>   * is still alive. In this case, try to adhere to the current favored nodes assignment as<a name="line.98"></a>
-<span class="sourceLineNo">099</span>   * much as possible - i.e., if the current primary is gone, then make the secondary or<a name="line.99"></a>
-<span class="sourceLineNo">100</span>   * tertiary as the new host for the region (based on their current load). Note that we don't<a name="line.100"></a>
-<span class="sourceLineNo">101</span>   * change the favored node assignments here (even though one or more favored node is<a name="line.101"></a>
-<span class="sourceLineNo">102</span>   * currently down). That will be done by the admin operations.<a name="line.102"></a>
-<span class="sourceLineNo">103</span>   *<a name="line.103"></a>
-<span class="sourceLineNo">104</span>   * 2. The regions that currently don't have favored node assignments. Generate favored nodes<a name="line.104"></a>
-<span class="sourceLineNo">105</span>   * for them and then assign. Generate the primary fn in round robin fashion and generate<a name="line.105"></a>
-<span class="sourceLineNo">106</span>   * secondary and tertiary as per favored nodes constraints.<a name="line.106"></a>
-<span class="sourceLineNo">107</span>   */<a name="line.107"></a>
-<span class="sourceLineNo">108</span>  @Override<a name="line.108"></a>
-<span class="sourceLineNo">109</span>  public Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; roundRobinAssignment(List&lt;HRegionInfo&gt; regions,<a name="line.109"></a>
-<span class="sourceLineNo">110</span>      List&lt;ServerName&gt; servers) throws HBaseIOException {<a name="line.110"></a>
-<span class="sourceLineNo">111</span><a name="line.111"></a>
-<span class="sourceLineNo">112</span>    metricsBalancer.incrMiscInvocations();<a name="line.112"></a>
-<span class="sourceLineNo">113</span><a name="line.113"></a>
-<span class="sourceLineNo">114</span>    Set&lt;HRegionInfo&gt; regionSet = Sets.newHashSet(regions);<a name="line.114"></a>
-<span class="sourceLineNo">115</span>    Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; assignmentMap = assignMasterRegions(regions, servers);<a name="line.115"></a>
-<span class="sourceLineNo">116</span>    if (assignmentMap != null &amp;&amp; !assignmentMap.isEmpty()) {<a name="line.116"></a>
-<span class="sourceLineNo">117</span>      servers = new ArrayList&lt;&gt;(servers);<a name="line.117"></a>
-<span class="sourceLineNo">118</span>      // Guarantee not to put other regions on master<a name="line.118"></a>
-<span class="sourceLineNo">119</span>      servers.remove(masterServerName);<a name="line.119"></a>
-<span class="sourceLineNo">120</span>      List&lt;HRegionInfo&gt; masterRegions = assignmentMap.get(masterServerName);<a name="line.120"></a>
-<span class="sourceLineNo">121</span>      if (!masterRegions.isEmpty()) {<a name="line.121"></a>
-<span class="sourceLineNo">122</span>        for (HRegionInfo region: masterRegions) {<a name="line.122"></a>
-<span class="sourceLineNo">123</span>          regionSet.remove(region);<a name="line.123"></a>
-<span class="sourceLineNo">124</span>        }<a name="line.124"></a>
-<span class="sourceLineNo">125</span>      }<a name="line.125"></a>
-<span class="sourceLineNo">126</span>    }<a name="line.126"></a>
-<span class="sourceLineNo">127</span><a name="line.127"></a>
-<span class="sourceLineNo">128</span>    if (regionSet.isEmpty()) {<a name="line.128"></a>
-<span class="sourceLineNo">129</span>      return assignmentMap;<a name="line.129"></a>
-<span class="sourceLineNo">130</span>    }<a name="line.130"></a>
-<span class="sourceLineNo">131</span><a name="line.131"></a>
-<span class="sourceLineNo">132</span>    try {<a name="line.132"></a>
-<span class="sourceLineNo">133</span>      FavoredNodeAssignmentHelper helper =<a name="line.133"></a>
-<span class="sourceLineNo">134</span>          new FavoredNodeAssignmentHelper(servers, fnm.getRackManager());<a name="line.134"></a>
-<span class="sourceLineNo">135</span>      helper.initialize();<a name="line.135"></a>
-<span class="sourceLineNo">136</span><a name="line.136"></a>
-<span class="sourceLineNo">137</span>      Set&lt;HRegionInfo&gt; systemRegions = FavoredNodesManager.filterNonFNApplicableRegions(regionSet);<a name="line.137"></a>
-<span class="sourceLineNo">138</span>      regionSet.removeAll(systemRegions);<a name="line.138"></a>
-<span class="sourceLineNo">139</span><a name="line.139"></a>
-<span class="sourceLineNo">140</span>      // Assign all system regions<a name="line.140"></a>
-<span class="sourceLineNo">141</span>      Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; systemAssignments =<a name="line.141"></a>
-<span class="sourceLineNo">142</span>        super.roundRobinAssignment(Lists.newArrayList(systemRegions), servers);<a name="line.142"></a>
-<span class="sourceLineNo">143</span><a name="line.143"></a>
-<span class="sourceLineNo">144</span>      // Segregate favored and non-favored nodes regions and assign accordingly.<a name="line.144"></a>
-<span class="sourceLineNo">145</span>      Pair&lt;Map&lt;ServerName,List&lt;HRegionInfo&gt;&gt;, List&lt;HRegionInfo&gt;&gt; segregatedRegions =<a name="line.145"></a>
-<span class="sourceLineNo">146</span>        segregateRegionsAndAssignRegionsWithFavoredNodes(regionSet, servers);<a name="line.146"></a>
-<span class="sourceLineNo">147</span>      Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; regionsWithFavoredNodesMap = segregatedRegions.getFirst();<a name="line.147"></a>
-<span class="sourceLineNo">148</span>      Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; regionsWithoutFN =<a name="line.148"></a>
-<span class="sourceLineNo">149</span>        generateFNForRegionsWithoutFN(helper, segregatedRegions.getSecond());<a name="line.149"></a>
-<span class="sourceLineNo">150</span><a name="line.150"></a>
-<span class="sourceLineNo">151</span>      // merge the assignment maps<a name="line.151"></a>
-<span class="sourceLineNo">152</span>      mergeAssignmentMaps(assignmentMap, systemAssignments);<a name="line.152"></a>
-<span class="sourceLineNo">153</span>      mergeAssignmentMaps(assignmentMap, regionsWithFavoredNodesMap);<a name="line.153"></a>
-<span class="sourceLineNo">154</span>      mergeAssignmentMaps(assignmentMap, regionsWithoutFN);<a name="line.154"></a>
-<span class="sourceLineNo">155</span><a name="line.155"></a>
-<span class="sourceLineNo">156</span>    } catch (Exception ex) {<a name="line.156"></a>
-<span class="sourceLineNo">157</span>      throw new HBaseIOException("Encountered exception while doing favored-nodes assignment "<a name="line.157"></a>
-<span class="sourceLineNo">158</span>        + ex + " Falling back to regular assignment", ex);<a name="line.158"></a>
-<span class="sourceLineNo">159</span>    }<a name="line.159"></a>
-<span class="sourceLineNo">160</span>    return assignmentMap;<a name="line.160"></a>
-<span class="sourceLineNo">161</span>  }<a name="line.161"></a>
-<span class="sourceLineNo">162</span><a name="line.162"></a>
-<span class="sourceLineNo">163</span>  private void mergeAssignmentMaps(Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; assignmentMap,<a name="line.163"></a>
-<span class="sourceLineNo">164</span>      Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; otherAssignments) {<a name="line.164"></a>
-<span class="sourceLineNo">165</span><a name="line.165"></a>
-<span class="sourceLineNo">166</span>    if (otherAssignments == null || otherAssignments.isEmpty()) {<a name="line.166"></a>
-<span class="sourceLineNo">167</span>      return;<a name="line.167"></a>
-<span class="sourceLineNo">168</span>    }<a name="line.168"></a>
-<span class="sourceLineNo">169</span><a name="line.169"></a>
-<span class="sourceLineNo">170</span>    for (Entry&lt;ServerName, List&lt;HRegionInfo&gt;&gt; entry : otherAssignments.entrySet()) {<a name="line.170"></a>
-<span class="sourceLineNo">171</span>      ServerName sn = entry.getKey();<a name="line.171"></a>
-<span class="sourceLineNo">172</span>      List&lt;HRegionInfo&gt; regionsList = entry.getValue();<a name="line.172"></a>
-<span class="sourceLineNo">173</span>      if (assignmentMap.get(sn) == null) {<a name="line.173"></a>
-<span class="sourceLineNo">174</span>        assignmentMap.put(sn, Lists.newArrayList(regionsList));<a name="line.174"></a>
-<span class="sourceLineNo">175</span>      } else {<a name="line.175"></a>
-<span class="sourceLineNo">176</span>        assignmentMap.get(sn).addAll(regionsList);<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>  }<a name="line.179"></a>
-<span class="sourceLineNo">180</span><a name="line.180"></a>
-<span class="sourceLineNo">181</span>  private Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; generateFNForRegionsWithoutFN(<a name="line.181"></a>
-<span class="sourceLineNo">182</span>      FavoredNodeAssignmentHelper helper, List&lt;HRegionInfo&gt; regions) throws IOException {<a name="line.182"></a>
-<span class="sourceLineNo">183</span><a name="line.183"></a>
-<span class="sourceLineNo">184</span>    Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; assignmentMap = Maps.newHashMap();<a name="line.184"></a>
-<span class="sourceLineNo">185</span>    Map&lt;HRegionInfo, List&lt;ServerName&gt;&gt; regionsNoFNMap;<a name="line.185"></a>
-<span class="sourceLineNo">186</span><a name="line.186"></a>
-<span class="sourceLineNo">187</span>    if (regions.size() &gt; 0) {<a name="line.187"></a>
-<span class="sourceLineNo">188</span>      regionsNoFNMap = helper.generateFavoredNodesRoundRobin(assignmentMap, regions);<a name="line.188"></a>
-<span class="sourceLineNo">189</span>      fnm.updateFavoredNodes(regionsNoFNMap);<a name="line.189"></a>
-<span class="sourceLineNo">190</span>    }<a name="line.190"></a>
-<span class="sourceLineNo">191</span>    return assignmentMap;<a name="line.191"></a>
-<span class="sourceLineNo">192</span>  }<a name="line.192"></a>
-<span class="sourceLineNo">193</span><a name="line.193"></a>
-<span class="sourceLineNo">194</span>  /*<a name="line.194"></a>
-<span class="sourceLineNo">195</span>   * Return a pair - one with assignments when favored nodes are present and another with regions<a name="line.195"></a>
-<span class="sourceLineNo">196</span>   * without favored nodes.<a name="line.196"></a>
-<span class="sourceLineNo">197</span>   */<a name="line.197"></a>
-<span class="sourceLineNo">198</span>  private Pair&lt;Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt;, List&lt;HRegionInfo&gt;&gt;<a name="line.198"></a>
-<span class="sourceLineNo">199</span>  segregateRegionsAndAssignRegionsWithFavoredNodes(Collection&lt;HRegionInfo&gt; regions,<a name="line.199"></a>
-<span class="sourceLineNo">200</span>      List&lt;ServerName&gt; onlineServers) throws HBaseIOException {<a name="line.200"></a>
-<span class="sourceLineNo">201</span><a name="line.201"></a>
-<span class="sourceLineNo">202</span>    // Since we expect FN to be present most of the time, lets create map with same size<a name="line.202"></a>
-<span class="sourceLineNo">203</span>    Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; assignmentMapForFavoredNodes =<a name="line.203"></a>
-<span class="sourceLineNo">204</span>        new HashMap&lt;&gt;(onlineServers.size());<a name="line.204"></a>
-<span class="sourceLineNo">205</span>    List&lt;HRegionInfo&gt; regionsWithNoFavoredNodes = new ArrayList&lt;&gt;();<a name="line.205"></a>
-<span class="sourceLineNo">206</span><a name="line.206"></a>
-<span class="sourceLineNo">207</span>    for (HRegionInfo region : regions) {<a name="line.207"></a>
-<span class="sourceLineNo">208</span>      List&lt;ServerName&gt; favoredNodes = fnm.getFavoredNodes(region);<a name="line.208"></a>
-<span class="sourceLineNo">209</span>      ServerName primaryHost = null;<a name="line.209"></a>
-<span class="sourceLineNo">210</span>      ServerName secondaryHost = null;<a name="line.210"></a>
-<span class="sourceLineNo">211</span>      ServerName tertiaryHost = null;<a name="line.211"></a>
-<span class="sourceLineNo">212</span><a name="line.212"></a>
-<span class="sourceLineNo">213</span>      if (favoredNodes != null &amp;&amp; !favoredNodes.isEmpty()) {<a name="line.213"></a>
-<span class="sourceLineNo">214</span>        for (ServerName s : favoredNodes) {<a name="line.214"></a>
-<span class="sourceLineNo">215</span>          ServerName serverWithLegitStartCode = getServerFromFavoredNode(onlineServers, s);<a name="line.215"></a>
-<span class="sourceLineNo">216</span>          if (serverWithLegitStartCode != null) {<a name="line.216"></a>
-<span class="sourceLineNo">217</span>            FavoredNodesPlan.Position position =<a name="line.217"></a>
-<span class="sourceLineNo">218</span>                FavoredNodesPlan.getFavoredServerPosition(favoredNodes, s);<a name="line.218"></a>
-<span class="sourceLineNo">219</span>            if (Position.PRIMARY.equals(position)) {<a name="line.219"></a>
-<span class="sourceLineNo">220</span>              primaryHost = serverWithLegitStartCode;<a name="line.220"></a>
-<span class="sourceLineNo">221</span>            } else if (Position.SECONDARY.equals(position)) {<a name="line.221"></a>
-<span class="sourceLineNo">222</span>              secondaryHost = serverWithLegitStartCode;<a name="line.222"></a>
-<span class="sourceLineNo">223</span>            } else if (Position.TERTIARY.equals(position)) {<a name="line.223"></a>
-<span class="sourceLineNo">224</span>              tertiaryHost = serverWithLegitStartCode;<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>        }<a name="line.227"></a>
-<span class="sourceLineNo">228</span>        assignRegionToAvailableFavoredNode(assignmentMapForFavoredNodes, region, primaryHost,<a name="line.228"></a>
-<span class="sourceLineNo">229</span>            secondaryHost, tertiaryHost);<a name="line.229"></a>
-<span class="sourceLineNo">230</span>      } else {<a name="line.230"></a>
-<span class="sourceLineNo">231</span>        regionsWithNoFavoredNodes.add(region);<a name="line.231"></a>
-<span class="sourceLineNo">232</span>      }<a name="line.232"></a>
-<span class="sourceLineNo">233</span>    }<a name="line.233"></a>
-<span class="sourceLineNo">234</span>    return new Pair&lt;&gt;(assignmentMapForFavoredNodes, regionsWithNoFavoredNodes);<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>  private void addRegionToMap(Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; assignmentMapForFavoredNodes,<a name="line.237"></a>
-<span class="sourceLineNo">238</span>      HRegionInfo region, ServerName host) {<a name="line.238"></a>
-<span class="sourceLineNo">239</span><a name="line.239"></a>
-<span class="sourceLineNo">240</span>    List&lt;HRegionInfo&gt; regionsOnServer;<a name="line.240"></a>
-<span class="sourceLineNo">241</span>    if ((regionsOnServer = assignmentMapForFavoredNodes.get(host)) == null) {<a name="line.241"></a>
-<span class="sourceLineNo">242</span>      regionsOnServer = Lists.newArrayList();<a name="line.242"></a>
-<span class="sourceLineNo">243</span>      assignmentMapForFavoredNodes.put(host, regionsOnServer);<a name="line.243"></a>
-<span class="sourceLineNo">244</span>    }<a name="line.244"></a>
-<span class="sourceLineNo">245</span>    regionsOnServer.add(region);<a name="line.245"></a>
-<span class="sourceLineNo">246</span>  }<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>   * Get the ServerName for the FavoredNode. Since FN's startcode is -1, we could want to get the<a name="line.249"></a>
-<span class="sourceLineNo">250</span>   * ServerName with the correct start code from the list of provided servers.<a name="line.250"></a>
-<span class="sourceLineNo">251</span>   */<a name="line.251"></a>
-<span class="sourceLineNo">252</span>  private ServerName getServerFromFavoredNode(List&lt;ServerName&gt; servers, ServerName fn) {<a name="line.252"></a>
-<span class="sourceLineNo">253</span>    for (ServerName server : servers) {<a name="line.253"></a>
-<span class="sourceLineNo">254</span>      if (ServerName.isSameHostnameAndPort(fn, server)) {<a name="line.254"></a>
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+<span class="sourceLineNo">046</span>import org.apache.hadoop.hbase.master.LoadBalancer;<a name="line.46"></a>
+<span class="sourceLineNo">047</span>import org.apache.hadoop.hbase.master.MasterServices;<a name="line.47"></a>
+<span class="sourceLineNo">048</span>import org.apache.hadoop.hbase.master.RegionPlan;<a name="line.48"></a>
+<span class="sourceLineNo">049</span>import org.apache.hadoop.hbase.util.Pair;<a name="line.49"></a>
+<span class="sourceLineNo">050</span><a name="line.50"></a>
+<span class="sourceLineNo">051</span>import org.apache.hadoop.hbase.shaded.com.google.common.collect.Lists;<a name="line.51"></a>
+<span class="sourceLineNo">052</span>import org.apache.hadoop.hbase.shaded.com.google.common.collect.Maps;<a name="line.52"></a>
+<span class="sourceLineNo">053</span>import org.apache.hadoop.hbase.shaded.com.google.common.collect.Sets;<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> * An implementation of the {@link org.apache.hadoop.hbase.master.LoadBalancer} that<a name="line.56"></a>
+<span class="sourceLineNo">057</span> * assigns favored nodes for each region. There is a Primary RegionServer that hosts<a name="line.57"></a>
+<span class="sourceLineNo">058</span> * the region, and then there is Secondary and Tertiary RegionServers. Currently, the<a name="line.58"></a>
+<span class="sourceLineNo">059</span> * favored nodes information is used in creating HDFS files - the Primary RegionServer<a name="line.59"></a>
+<span class="sourceLineNo">060</span> * passes the primary, secondary, tertiary node addresses as hints to the<a name="line.60"></a>
+<span class="sourceLineNo">061</span> * DistributedFileSystem API for creating files on the filesystem. These nodes are<a name="line.61"></a>
+<span class="sourceLineNo">062</span> * treated as hints by the HDFS to place the blocks of the file. This alleviates the<a name="line.62"></a>
+<span class="sourceLineNo">063</span> * problem to do with reading from remote nodes (since we can make the Secondary<a name="line.63"></a>
+<span class="sourceLineNo">064</span> * RegionServer as the new Primary RegionServer) after a region is recovered. This<a name="line.64"></a>
+<span class="sourceLineNo">065</span> * should help provide consistent read latencies for the regions even when their<a name="line.65"></a>
+<span class="sourceLineNo">066</span> * primary region servers die. This provides two<a name="line.66"></a>
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+<span class="sourceLineNo">068</span> *<a name="line.68"></a>
+<span class="sourceLineNo">069</span> */<a name="line.69"></a>
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+<span class="sourceLineNo">072</span><a name="line.72"></a>
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+<span class="sourceLineNo">075</span><a name="line.75"></a>
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+<span class="sourceLineNo">088</span><a name="line.88"></a>
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+<span class="sourceLineNo">103</span>   * currently down). That will be done by the admin operations.<a name="line.103"></a>
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+<span class="sourceLineNo">119</span>      // Guarantee not to put other regions on master<a name="line.119"></a>
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+<span class="sourceLineNo">122</span>      if (!masterRegions.isEmpty()) {<a name="line.122"></a>
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+<span class="sourceLineNo">128</span><a name="line.128"></a>
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+<span class="sourceLineNo">132</span><a name="line.132"></a>
+<span class="sourceLineNo">133</span>    try {<a name="line.133"></a>
+<span class="sourceLineNo">134</span>      FavoredNodeAssignmentHelper helper =<a name="line.134"></a>
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+<span class="sourceLineNo">137</span><a name="line.137"></a>
+<span class="sourceLineNo">138</span>      Set&lt;HRegionInfo&gt; systemRegions = FavoredNodesManager.filterNonFNApplicableRegions(regionSet);<a name="line.138"></a>
+<span class="sourceLineNo">139</span>      regionSet.removeAll(systemRegions);<a name="line.139"></a>
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+<span class="sourceLineNo">367</span>  @Override<a name="line.367"></a>
+<span class="sourceLineNo">368</span>  public Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; retainAssignment(Map&lt;HRegionInfo, ServerName&gt; regions,<a name="line.368"></a>
+<span class="sourceLineNo">369</span>      List&lt;ServerName&gt; servers) throws HBaseIOException {<a name="line.369"></a>
+<span class="sourceLineNo">370</span><a name="line.370"></a>
+<span class="sourceLineNo">371</span>    Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; assignmentMap = Maps.newHashMap();<a name="line.371"></a>
+<span class="sourceLineNo">372</span>    Map&lt;ServerName, List&lt;HRegionInfo&gt;&gt; result = super.retainAssignment(regions, servers);<a name="line.372"></a>
+<span class="sourceLineNo">373</span>    if (result == null || result.isEmpty()) {<a name="line.373"></a>
+<span class="sourceLineNo">374</span>      LOG.warn("Nothing to assign to, probably no servers or no regions");<a name="line.374"></a>
+<span class="sourceLineNo">375</span>      return null;<a name="line.375"></a>
+<span class="sourceLineNo">376</span>    }<a name="line.376"></a>
+<span class="sourceLineNo">377</span><a name="line.377"></a>
+<span class="sourceLineNo">378</span>    // Guarantee not to put other regions on master<a name="line.378"></a>
+<span class="sourceLineNo">379</span>    if (servers != null &amp;&amp; servers.contains(masterServerName)) {<a name="line.379"></a>
+<span class="sourceLineNo">380</span>      servers = new ArrayList&lt;&gt;(servers);<a name="line.380"></a>
+<span class="sourceLineNo">381</span>      servers.remove(masterServerName);<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>    // Lets check if favored nodes info is in META, if not generate now.<a name="line.384"></a>
+<span class="sourceLineNo">385</span>    FavoredNodeAssignmentHelper helper = new FavoredNodeAssignmentHelper(servers, getConf());<a name="line.385"></a>
+<span class="sourceLineNo">386</span>    helper.initialize();<a name="line.386"></a>
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-<span class="sourceLineNo">388</span>    try {<a name="line.388"></a>
-<span class="sourceLineNo">389</span>      for (Entry&lt;ServerName, List&lt;HRegionInfo&gt;&gt; entry : result.entrySet()) {<a name="line.389"></a>
+<span class="sourceLineNo">388</span>    LOG.debug("Generating favored nodes for regions missing them.");<a name="line.388"></a>
+<span class="sourceLineNo">389</span>    Map&lt;HRegionInfo, List&lt;ServerName&gt;&gt; regionFNMap = Maps.newHashMap();<a name="line.389"></a>
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-<span class="sourceLineNo">391</span>        ServerName sn = entry.getKey();<a name="line.391"></a>
-<span class="sourceLineNo">392</span>        ServerName primary = ServerName.valueOf(sn.getHostname(), sn.getPort(), NON_STARTCODE);<a name="line.392"></a>
+<span class="sourceLineNo">391</span>    try {<a name="line.391"></a>
+<span class="sourceLineNo">392</span>      for (Entry&lt;ServerName, List&lt;HRegionInfo&gt;&gt; entry : result.entrySet()) {<a name="line.392"></a>
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-<span class="sourceLineNo">400</span>              LOG.debug("Generating favored nodes for: " + hri + " with primary: " + primary);<a name="line.400"></a>
-<span class="sourceLineNo">401</span>              ServerName[] secondaryAndTertiaryNodes = helper.getSecondaryAndTertiary(hri, primary);<a name="line.401"></a>
-<span class="sourceLineNo">402</span>              if (secondaryAndTertiaryNodes != null &amp;&amp; secondaryAndTertiaryNodes.length == 2) {<a name="line.402"></a>
-<span class="sourceLineNo">403</span>                List&lt;ServerName&gt; newFavoredNodes = Lists.newArrayList();<a name="line.403"></a>
-<span class="sourceLineNo">404</span>                newFavoredNodes.add(primary);<a name="line.404"></a>
-<span class="sourceLineNo">405</span>                newFavoredNodes.add(ServerName.valueOf(secondaryAndTertiaryNodes[0].getHostname(),<a name="line.405"></a>
-<span class="sourceLineNo">406</span>                    secondaryAndTertiaryNodes[0].getPort(), NON_STARTCODE));<a name="line.406"></a>
-<span class="sourceLineNo">407</span>                newFavoredNodes.add(ServerName.valueOf(secondaryAndTertiaryNodes[1].getHostname(),<a name="line.407"></a>
-<span class="sourceLineNo">408</span>                    secondaryAndTertiaryNodes[1].getPort(), NON_STARTCODE));<a name="line.408"></a>
-<span class="sourceLineNo">409</span>                regionFNMap.put(hri, newFavoredNodes);<a name="line.409"></a>
-<span class="sourceLineNo">410</span>                addRegionToMap(assignmentMap, hri, sn);<a name="line.410"></a>
-<span class="sourceLineNo">411</span><a name="line.411"></a>
-<span class="sourceLineNo">412</span>              } else {<a name="line.412"></a>
-<span class="sourceLineNo">413</span>                throw new HBaseIOException("Cannot generate secondary/tertiary FN for " + hri<a name="line.413"></a>
-<span class="sourceLineNo">414</span>                  + " generated "<a name="line.414"></a>
-<span class="sourceLineNo">415</span>                  + (secondaryAndTertiaryNodes != null ? secondaryAndTertiaryNodes : " nothing"));<a name="line.415"></a>
-<span class="sourceLineNo">416</span>              }<a name="line.416"></a>
-<span class="sourceLineNo">417</span>            } else {<a name="line.417"></a>
-<span class="sourceLineNo">418</span>              List&lt;ServerName&gt; onlineFN = getOnlineFavoredNodes(servers, favoredNodes);<a name="line.418"></a>
-<span class="sourceLineNo">419</span>              if (onlineFN.isEmpty()) {<a name="line.419"></a>
-<span class="sourceLineNo">420</span>                // All favored nodes are dead, lets assign it to BOGUS<a name="line.420"></a>
-<span class="sourceLineNo">421</span>                addRegionToMap(assignmentMap, hri, BOGUS_SERVER_NAME);<a name="line.421"></a>
-<span class="sourceLineNo">422</span>              } else {<a name="line.422"></a>
-<span class="sourceLineNo">423</span>                // Is primary not on FN? Less likely, but we can still take care of this.<a name="line.423"></a>
-<span class="sourceLineNo">424</span>                if (FavoredNodesPlan.getFavoredServerPosition(favoredNodes, sn) != null) {<a name="line.424"></a>
-<span class="sourceLineNo">425</span>                  addRegionToMap(assignmentMap, hri, sn);<a name="line.425"></a>
-<span class="sourceLineNo">426</span>                } else {<a name="line.426"></a>
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-<span class="sourceLineNo">428</span>                  LOG.warn("Region: " + hri + " not hosted on favored nodes: " + favoredNodes<a name="line.428"></a>
-<span class="sourceLineNo">429</span>                    + " current: " + sn + " moving to: " + destination);<a name="line.429"></a>
-<span class="sourceLineNo">430</span>                  addRegionToMap(assignmentMap, hri, destination);<a name="line.430"></a>
-<span class="sourceLineNo">431</span>                }<a name="line.431"></a>
-<span class="sourceLineNo">432</span>              }<a name="line.432"></a>
-<span class="sourceLineNo">433</span>            }<a name="line.433"></a>
-<span class="sourceLineNo">434</span>          } else {<a name="line.434"></a>
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-<span class="sourceLineNo">436</span>          }<a name="line.436"></a>
-<span class="sourceLineNo">437</span>        }<a name="line.437"></a>
-<span class="sourceLineNo">438</span>      }<a name="line.438"></a>
-<span class="sourceLineNo">439</span><a name="line.439"></a>
-<span class="sourceLineNo">440</span>      if (!regionFNMap.isEmpty()) {<a name="line.440"></a>
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-<span class="sourceLineNo">442</span>        fnm.updateFavoredNodes(regionFNMap);<a name="line.442"></a>
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-<span class="sourceLineNo">444</span><a name="line.444"></a>
-<span class="sourceLineNo">445</span>    } catch (IOException e) {<a name="line.445"></a>
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-<span class="sourceLineNo">448</span><a name="line.448"></a>
-<span class="sourceLineNo">449</span>    return assignmentMap;<a name="line.449"></a>
-<span class="sourceLineNo">450</span>  }<a name="line.450"></a>
+<span class="sourceLineNo">394</span>        ServerName sn = entry.getKey();<a name="line.394"></a>
+<span class="sourceLineNo">395</span>        ServerName primary = ServerName.valueOf(sn.getHostname(), sn.getPort(), NON_STARTCODE);<a name="line.395"></a>
+<span class="sourceLineNo">396</span><a name="line.396"></a>
+<span class="sourceLineNo">397</span>        for (HRegionInfo hri : entry.getValue()) {<a name="line.397"></a>
+<span class="sourceLineNo">398</span><a name="line.398"></a>
+<span class="sourceLineNo">399</span>          if (FavoredNodesManager.isFavoredNodeApplicable(hri)) {<a name="line.399"></a>
+<span class="sourceLineNo">400</span>            List&lt;ServerName&gt; favoredNodes = fnm.getFavoredNodes(hri);<a name="line.400"></a>
+<span class="sourceLineNo">401</span>            if (favoredNodes == null || favoredNodes.size() &lt; FAVORED_NODES_NUM) {<a name="line.401"></a>
+<span class="sourceLineNo">402</span><a name="line.402"></a>
+<span class="sourceLineNo">403</span>              LOG.debug("Generating favored nodes for: " + hri + " with primary: " + primary);<a name="line.403"></a>
+<span class="sourceLineNo">404</span>              ServerName[] secondaryAndTertiaryNodes = helper.getSecondaryAndTertiary(hri, primary);<a name="line.404"></a>
+<span class="sourceLineNo">405</span>              if (secondaryAndTertiaryNodes != null &amp;&amp; secondaryAndTertiaryNodes.length == 2) {<a name="line.405"></a>
+<span class="sourceLineNo">406</span>                List&lt;ServerName&gt; newFavoredNodes = Lists.newArrayList();<a name="line.406"></a>
+<span class="sourceLineNo">407</span>                newFavoredNodes.add(primary);<a name="line.407"></a>
+<span class="sourceLineNo">408</span>                newFavoredNodes.add(ServerName.valueOf(secondaryAndTertiaryNodes[0].getHostname(),<a name="line.408"></a>
+<span class="sourceLineNo">409</span>                    secondaryAndTertiaryNodes[0].getPort(), NON_STARTCODE));<a name="line.409"></a>
+<span class="sourceLineNo">410</span>                newFavoredNodes.add(ServerName.valueOf(secondaryAndTertiaryNodes[1].getHostname(),<a name="line.410"></a>
+<span class="sourceLineNo">411</span>                    secondaryAndTertiaryNodes[1].getPort(), NON_STARTCODE));<a name="line.411"></a>
+<span class="sourceLineNo">412</span>                regionFNMap.put(hri, newFavoredNodes);<a name="line.412"></a>
+<span class="sourceLineNo">413</span>                addRegionToMap(assignmentMap, hri, sn);<a name="line.413"></a>
+<span class="sourceLineNo">414</span><a name="line.414"></a>
+<span class="sourceLineNo">415</span>              } else {<a name="line.415"></a>
+<span class="sourceLineNo">416</span>                throw new HBaseIOException("Cannot generate secondary/tertiary FN for " + hri<a name="line.416"></a>
+<span class="sourceLineNo">417</span>                  + " generated "<a name="line.417"></a>
+<span class="sourceLineNo">418</span>                  + (secondaryAndTertiaryNodes != null ? secondaryAndTertiaryNodes : " nothing"));<a name="line.418"></a>
+<span class="sourceLineNo">419</span>              }<a name="line.419"></a>
+<span class="sourceLineNo">420</span>            } else {<a name="line.420"></a>
+<span class="sourceLineNo">421</span>              List&lt;ServerName&gt; onlineFN = getOnlineFavoredNodes(servers, favoredNodes);<a name="line.421"></a>
+<span class="sourceLineNo">422</span>              if (onlineFN.isEmpty()) {<a name="line.422"></a>
+<span class="sourceLineNo">423</span>                // All favored nodes are dead, lets assign it to BOGUS<a name="line.423"></a>
+<span class="sourceLineNo">424</span>                addRegionToMap(assignmentMap, hri, BOGUS_SERVER_NAME);<a name="line.424"></a>
+<span class="sourceLineNo">425</span>              } else {<a name="line.425"></a>
+<span class="sourceLineNo">426</span>                // Is primary not on FN? Less likely, but we can still take care of this.<a name="line.426"></a>
+<span class="sourceLineNo">427</span>                if (FavoredNodesPlan.getFavoredServerPosition(favoredNodes, sn) != null) {<a name="line.427"></a>
+<span class="sourceLineNo">428</span>                  addRegionToMap(assignmentMap, hri, sn);<a name="line.428"></a>
+<span class="sourceLineNo">429</span>                } else {<a name="line.429"></a>
+<span class="sourceLineNo">430</span>                  ServerName destination = onlineFN.get(RANDOM.nextInt(onlineFN.size()));<a name="line.430"></a>
+<span class="sourceLineNo">431</span>                  LOG.warn("Region: " + hri + " not hosted on favored nodes: " + favoredNodes<a name="line.431"></a>
+<span class="sourceLineNo">432</span>                    + " current: " + sn + " moving to: " + destination);<a name="line.432"></a>
+<span class="sourceLineNo">433</span>                  addRegionToMap(assignmentMap, hri, destination);<a name="line.433"></a>
+<span class="sourceLineNo">434</span>                }<a name="line.434"></a>
+<span class="sourceLineNo">435</span>              }<a name="line.435"></a>
+<span class="sourceLineNo">436</span>            }<a name="line.436"></a>
+<span class="sourceLineNo">437</span>          } else {<a name="line.437"></a>
+<span class="sourceLineNo">438</span>            addRegionToMap(assignmentMap, hri, sn);<a name="line.438"></a>
+<span class="sourceLineNo">439</span>          }<a name="line.439"></a>
+<span class="sourceLineNo">440</span>        }<a name="line.440"></a>
+<span class="sourceLineNo">441</span>      }<a name="line.441"></a>
+<span class="sourceLineNo">442</span><a name="line.442"></a>
+<span class="sourceLineNo">443</span>      if (!regionFNMap.isEmpty()) {<a name="line.443"></a>
+<span class="sourceLineNo">444</span>        LOG.debug("Updating FN in meta for missing regions, count: " + regionFNMap.size());<a name="line.444"></a>
+<span class="sourceLineNo">445</span>        fnm.updateFavoredNodes(regionFNMap);<a name="line.445"></a>
+<span class="sourceLineNo">446</span>      }<a name="line.446"></a>
+<span class="sourceLineNo">447</span><a name="line.447"></a>
+<span class="sourceLineNo">448</span>    } catch (IOException e) {<a name="line.448"></a>
+<span class="sourceLineNo">449</span>      throw new HBaseIOException("Cannot generate/update FN for regions: " + regionFNMap.keySet());<a name="line.449"></a>
+<span class="sourceLineNo">450</span>    }<a name="line.450"></a>
 <span class="sourceLineNo">451</span><a name="line.451"></a>
-<span class="sourceLineNo">452</span>  /*<a name="line.452"></a>
-<span class="sourceLineNo">453</span>   * Return list of favored nodes that are online.<a name="line.453"></a>
-<span class="sourceLineNo">454</span>   */<a name="line.454"></a>
-<span class="sourceLineNo">455</span>  private List&lt;ServerName&gt; getOnlineFavoredNodes(List&lt;ServerName&gt; onlineServers,<a name="line.455"></a>
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-<span class="sourceLineNo">457</span>    if (serversWithoutStartCodes == null) {<a name="line.457"></a>
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-<span class="sourceLineNo">459</span>    } else {<a name="line.459"></a>
-<span class="sourceLineNo">460</span>      List&lt;ServerName&gt; result = Lists.newArrayList();<a name="line.460"></a>
-<span class="sourceLineNo">461</span>      for (ServerName sn : serversWithoutStartCodes) {<a name="line.461"></a>
-<span class="sourceLineNo">462</span>        for (ServerName online : onlineServers) {<a name="line.462"></a>
-<span class="sourceLineNo">463</span>          if (ServerName.isSameHostnameAndPort(sn, online)) {<a name="line.463"></a>
-<span class="sourceLineNo">464</span>            result.add(online);<a name="line.464"></a>
-<span class="sourceLineNo">465</span>          }<a name="line.465"></a>
-<span class="sourceLineNo">466</span>        }<a name="line.466"></a>
-<span class="sourceLineNo">467</span>      }<a name="line.467"></a>
-<span class="sourceLineNo">468</span>      return result;<a name="line.468"></a>
-<span class="sourceLineNo">469</span>    }<a name="line.469"></a>
-<span class="sourceLineNo">470</span>  }<a name="line.470"></a>
-<span class="sourceLineNo">471</span><a name="line.471"></a>
-<span class="sourceLineNo">472</span>  public synchronized List&lt;ServerName&gt; getFavoredNodes(HRegionInfo regionInfo) {<a name="line.472"></a>
-<span class="sourceLineNo">473</span>    return this.fnm.getFavoredNodes(regionInfo);<a name="line.473"></a>
-<span class="sourceLineNo">474</span>  }<a name="line.474"></a>
-<span class="sourceLineNo">475</span><a name="line.475"></a>
-<span class="sourceLineNo">476</span>  /*<a name="line.476"></a>
-<span class="sourceLineNo">477</span>   * Generate Favored Nodes for daughters during region split.<a name="line.477"></a>
-<span class="sourceLineNo">478</span>   *<a name="line.478"></a>
-<span class="sourceLineNo">479</span>   * If the parent does not have FN, regenerates them for the daughters.<a name="line.479"></a>
-<span class="sourceLineNo">480</span>   *<a name="line.480"></a>
-<span class="sourceLineNo">481</span>   * If the parent has FN, inherit two FN from parent for each daughter and generate the remaining.<a name="line.481"></a>
-<span class="sourceLineNo">482</span>   * The primary FN for both the daughters should be the same as parent. Inherit the secondary<a name="line.482"></a>
-<span class="sourceLineNo">483</span>   * FN from the parent but keep it different for each daughter. Choose the remaining FN<a name="line.483"></a>
-<span class="sourceLineNo">484</span>   * randomly. This would give us better distributi

<TRUNCATED>

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