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| <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><a name="line.19"></a> |
| <span class="sourceLineNo">020</span>package org.apache.hadoop.hbase.regionserver;<a name="line.20"></a> |
| <span class="sourceLineNo">021</span><a name="line.21"></a> |
| <span class="sourceLineNo">022</span>import org.apache.hbase.thirdparty.com.google.common.annotations.VisibleForTesting;<a name="line.22"></a> |
| <span class="sourceLineNo">023</span><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.util.ArrayList;<a name="line.25"></a> |
| <span class="sourceLineNo">026</span>import java.util.Comparator;<a name="line.26"></a> |
| <span class="sourceLineNo">027</span>import java.util.List;<a name="line.27"></a> |
| <span class="sourceLineNo">028</span>import java.util.PriorityQueue;<a name="line.28"></a> |
| <span class="sourceLineNo">029</span><a name="line.29"></a> |
| <span class="sourceLineNo">030</span>import org.apache.hadoop.hbase.Cell;<a name="line.30"></a> |
| <span class="sourceLineNo">031</span>import org.apache.hadoop.hbase.CellComparator;<a name="line.31"></a> |
| <span class="sourceLineNo">032</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.32"></a> |
| <span class="sourceLineNo">033</span>import org.slf4j.Logger;<a name="line.33"></a> |
| <span class="sourceLineNo">034</span>import org.slf4j.LoggerFactory;<a name="line.34"></a> |
| <span class="sourceLineNo">035</span>import org.apache.hadoop.hbase.regionserver.ScannerContext.NextState;<a name="line.35"></a> |
| <span class="sourceLineNo">036</span><a name="line.36"></a> |
| <span class="sourceLineNo">037</span>/**<a name="line.37"></a> |
| <span class="sourceLineNo">038</span> * Implements a heap merge across any number of KeyValueScanners.<a name="line.38"></a> |
| <span class="sourceLineNo">039</span> * <p><a name="line.39"></a> |
| <span class="sourceLineNo">040</span> * Implements KeyValueScanner itself.<a name="line.40"></a> |
| <span class="sourceLineNo">041</span> * <p><a name="line.41"></a> |
| <span class="sourceLineNo">042</span> * This class is used at the Region level to merge across Stores<a name="line.42"></a> |
| <span class="sourceLineNo">043</span> * and at the Store level to merge across the memstore and StoreFiles.<a name="line.43"></a> |
| <span class="sourceLineNo">044</span> * <p><a name="line.44"></a> |
| <span class="sourceLineNo">045</span> * In the Region case, we also need InternalScanner.next(List), so this class<a name="line.45"></a> |
| <span class="sourceLineNo">046</span> * also implements InternalScanner. WARNING: As is, if you try to use this<a name="line.46"></a> |
| <span class="sourceLineNo">047</span> * as an InternalScanner at the Store level, you will get runtime exceptions.<a name="line.47"></a> |
| <span class="sourceLineNo">048</span> */<a name="line.48"></a> |
| <span class="sourceLineNo">049</span>@InterfaceAudience.Private<a name="line.49"></a> |
| <span class="sourceLineNo">050</span>public class KeyValueHeap extends NonReversedNonLazyKeyValueScanner<a name="line.50"></a> |
| <span class="sourceLineNo">051</span> implements KeyValueScanner, InternalScanner {<a name="line.51"></a> |
| <span class="sourceLineNo">052</span> private static final Logger LOG = LoggerFactory.getLogger(KeyValueHeap.class);<a name="line.52"></a> |
| <span class="sourceLineNo">053</span> protected PriorityQueue<KeyValueScanner> heap = null;<a name="line.53"></a> |
| <span class="sourceLineNo">054</span> // Holds the scanners when a ever a eager close() happens. All such eagerly closed<a name="line.54"></a> |
| <span class="sourceLineNo">055</span> // scans are collected and when the final scanner.close() happens will perform the<a name="line.55"></a> |
| <span class="sourceLineNo">056</span> // actual close.<a name="line.56"></a> |
| <span class="sourceLineNo">057</span> protected List<KeyValueScanner> scannersForDelayedClose = null;<a name="line.57"></a> |
| <span class="sourceLineNo">058</span><a name="line.58"></a> |
| <span class="sourceLineNo">059</span> /**<a name="line.59"></a> |
| <span class="sourceLineNo">060</span> * The current sub-scanner, i.e. the one that contains the next key/value<a name="line.60"></a> |
| <span class="sourceLineNo">061</span> * to return to the client. This scanner is NOT included in {@link #heap}<a name="line.61"></a> |
| <span class="sourceLineNo">062</span> * (but we frequently add it back to the heap and pull the new winner out).<a name="line.62"></a> |
| <span class="sourceLineNo">063</span> * We maintain an invariant that the current sub-scanner has already done<a name="line.63"></a> |
| <span class="sourceLineNo">064</span> * a real seek, and that current.peek() is always a real key/value (or null)<a name="line.64"></a> |
| <span class="sourceLineNo">065</span> * except for the fake last-key-on-row-column supplied by the multi-column<a name="line.65"></a> |
| <span class="sourceLineNo">066</span> * Bloom filter optimization, which is OK to propagate to StoreScanner. In<a name="line.66"></a> |
| <span class="sourceLineNo">067</span> * order to ensure that, always use {@link #pollRealKV()} to update current.<a name="line.67"></a> |
| <span class="sourceLineNo">068</span> */<a name="line.68"></a> |
| <span class="sourceLineNo">069</span> protected KeyValueScanner current = null;<a name="line.69"></a> |
| <span class="sourceLineNo">070</span><a name="line.70"></a> |
| <span class="sourceLineNo">071</span> protected KVScannerComparator comparator;<a name="line.71"></a> |
| <span class="sourceLineNo">072</span><a name="line.72"></a> |
| <span class="sourceLineNo">073</span> /**<a name="line.73"></a> |
| <span class="sourceLineNo">074</span> * Constructor. This KeyValueHeap will handle closing of passed in<a name="line.74"></a> |
| <span class="sourceLineNo">075</span> * KeyValueScanners.<a name="line.75"></a> |
| <span class="sourceLineNo">076</span> * @param scanners<a name="line.76"></a> |
| <span class="sourceLineNo">077</span> * @param comparator<a name="line.77"></a> |
| <span class="sourceLineNo">078</span> */<a name="line.78"></a> |
| <span class="sourceLineNo">079</span> public KeyValueHeap(List<? extends KeyValueScanner> scanners,<a name="line.79"></a> |
| <span class="sourceLineNo">080</span> CellComparator comparator) throws IOException {<a name="line.80"></a> |
| <span class="sourceLineNo">081</span> this(scanners, new KVScannerComparator(comparator));<a name="line.81"></a> |
| <span class="sourceLineNo">082</span> }<a name="line.82"></a> |
| <span class="sourceLineNo">083</span><a name="line.83"></a> |
| <span class="sourceLineNo">084</span> /**<a name="line.84"></a> |
| <span class="sourceLineNo">085</span> * Constructor.<a name="line.85"></a> |
| <span class="sourceLineNo">086</span> * @param scanners<a name="line.86"></a> |
| <span class="sourceLineNo">087</span> * @param comparator<a name="line.87"></a> |
| <span class="sourceLineNo">088</span> * @throws IOException<a name="line.88"></a> |
| <span class="sourceLineNo">089</span> */<a name="line.89"></a> |
| <span class="sourceLineNo">090</span> KeyValueHeap(List<? extends KeyValueScanner> scanners,<a name="line.90"></a> |
| <span class="sourceLineNo">091</span> KVScannerComparator comparator) throws IOException {<a name="line.91"></a> |
| <span class="sourceLineNo">092</span> this.comparator = comparator;<a name="line.92"></a> |
| <span class="sourceLineNo">093</span> this.scannersForDelayedClose = new ArrayList<>(scanners.size());<a name="line.93"></a> |
| <span class="sourceLineNo">094</span> if (!scanners.isEmpty()) {<a name="line.94"></a> |
| <span class="sourceLineNo">095</span> this.heap = new PriorityQueue<>(scanners.size(), this.comparator);<a name="line.95"></a> |
| <span class="sourceLineNo">096</span> for (KeyValueScanner scanner : scanners) {<a name="line.96"></a> |
| <span class="sourceLineNo">097</span> if (scanner.peek() != null) {<a name="line.97"></a> |
| <span class="sourceLineNo">098</span> this.heap.add(scanner);<a name="line.98"></a> |
| <span class="sourceLineNo">099</span> } else {<a name="line.99"></a> |
| <span class="sourceLineNo">100</span> this.scannersForDelayedClose.add(scanner);<a name="line.100"></a> |
| <span class="sourceLineNo">101</span> }<a name="line.101"></a> |
| <span class="sourceLineNo">102</span> }<a name="line.102"></a> |
| <span class="sourceLineNo">103</span> this.current = pollRealKV();<a name="line.103"></a> |
| <span class="sourceLineNo">104</span> }<a name="line.104"></a> |
| <span class="sourceLineNo">105</span> }<a name="line.105"></a> |
| <span class="sourceLineNo">106</span><a name="line.106"></a> |
| <span class="sourceLineNo">107</span> @Override<a name="line.107"></a> |
| <span class="sourceLineNo">108</span> public Cell peek() {<a name="line.108"></a> |
| <span class="sourceLineNo">109</span> if (this.current == null) {<a name="line.109"></a> |
| <span class="sourceLineNo">110</span> return null;<a name="line.110"></a> |
| <span class="sourceLineNo">111</span> }<a name="line.111"></a> |
| <span class="sourceLineNo">112</span> return this.current.peek();<a name="line.112"></a> |
| <span class="sourceLineNo">113</span> }<a name="line.113"></a> |
| <span class="sourceLineNo">114</span><a name="line.114"></a> |
| <span class="sourceLineNo">115</span> boolean isLatestCellFromMemstore() {<a name="line.115"></a> |
| <span class="sourceLineNo">116</span> return !this.current.isFileScanner();<a name="line.116"></a> |
| <span class="sourceLineNo">117</span> }<a name="line.117"></a> |
| <span class="sourceLineNo">118</span><a name="line.118"></a> |
| <span class="sourceLineNo">119</span> @Override<a name="line.119"></a> |
| <span class="sourceLineNo">120</span> public Cell next() throws IOException {<a name="line.120"></a> |
| <span class="sourceLineNo">121</span> if(this.current == null) {<a name="line.121"></a> |
| <span class="sourceLineNo">122</span> return null;<a name="line.122"></a> |
| <span class="sourceLineNo">123</span> }<a name="line.123"></a> |
| <span class="sourceLineNo">124</span> Cell kvReturn = this.current.next();<a name="line.124"></a> |
| <span class="sourceLineNo">125</span> Cell kvNext = this.current.peek();<a name="line.125"></a> |
| <span class="sourceLineNo">126</span> if (kvNext == null) {<a name="line.126"></a> |
| <span class="sourceLineNo">127</span> this.scannersForDelayedClose.add(this.current);<a name="line.127"></a> |
| <span class="sourceLineNo">128</span> this.current = null;<a name="line.128"></a> |
| <span class="sourceLineNo">129</span> this.current = pollRealKV();<a name="line.129"></a> |
| <span class="sourceLineNo">130</span> } else {<a name="line.130"></a> |
| <span class="sourceLineNo">131</span> KeyValueScanner topScanner = this.heap.peek();<a name="line.131"></a> |
| <span class="sourceLineNo">132</span> // no need to add current back to the heap if it is the only scanner left<a name="line.132"></a> |
| <span class="sourceLineNo">133</span> if (topScanner != null && this.comparator.compare(kvNext, topScanner.peek()) >= 0) {<a name="line.133"></a> |
| <span class="sourceLineNo">134</span> this.heap.add(this.current);<a name="line.134"></a> |
| <span class="sourceLineNo">135</span> this.current = null;<a name="line.135"></a> |
| <span class="sourceLineNo">136</span> this.current = pollRealKV();<a name="line.136"></a> |
| <span class="sourceLineNo">137</span> }<a name="line.137"></a> |
| <span class="sourceLineNo">138</span> }<a name="line.138"></a> |
| <span class="sourceLineNo">139</span> return kvReturn;<a name="line.139"></a> |
| <span class="sourceLineNo">140</span> }<a name="line.140"></a> |
| <span class="sourceLineNo">141</span><a name="line.141"></a> |
| <span class="sourceLineNo">142</span> /**<a name="line.142"></a> |
| <span class="sourceLineNo">143</span> * Gets the next row of keys from the top-most scanner.<a name="line.143"></a> |
| <span class="sourceLineNo">144</span> * <p><a name="line.144"></a> |
| <span class="sourceLineNo">145</span> * This method takes care of updating the heap.<a name="line.145"></a> |
| <span class="sourceLineNo">146</span> * <p><a name="line.146"></a> |
| <span class="sourceLineNo">147</span> * This can ONLY be called when you are using Scanners that implement InternalScanner as well as<a name="line.147"></a> |
| <span class="sourceLineNo">148</span> * KeyValueScanner (a {@link StoreScanner}).<a name="line.148"></a> |
| <span class="sourceLineNo">149</span> * @return true if more rows exist after this one, false if scanner is done<a name="line.149"></a> |
| <span class="sourceLineNo">150</span> */<a name="line.150"></a> |
| <span class="sourceLineNo">151</span> @Override<a name="line.151"></a> |
| <span class="sourceLineNo">152</span> public boolean next(List<Cell> result, ScannerContext scannerContext) throws IOException {<a name="line.152"></a> |
| <span class="sourceLineNo">153</span> if (this.current == null) {<a name="line.153"></a> |
| <span class="sourceLineNo">154</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.154"></a> |
| <span class="sourceLineNo">155</span> }<a name="line.155"></a> |
| <span class="sourceLineNo">156</span> InternalScanner currentAsInternal = (InternalScanner)this.current;<a name="line.156"></a> |
| <span class="sourceLineNo">157</span> boolean moreCells = currentAsInternal.next(result, scannerContext);<a name="line.157"></a> |
| <span class="sourceLineNo">158</span> Cell pee = this.current.peek();<a name="line.158"></a> |
| <span class="sourceLineNo">159</span><a name="line.159"></a> |
| <span class="sourceLineNo">160</span> /*<a name="line.160"></a> |
| <span class="sourceLineNo">161</span> * By definition, any InternalScanner must return false only when it has no<a name="line.161"></a> |
| <span class="sourceLineNo">162</span> * further rows to be fetched. So, we can close a scanner if it returns<a name="line.162"></a> |
| <span class="sourceLineNo">163</span> * false. All existing implementations seem to be fine with this. It is much<a name="line.163"></a> |
| <span class="sourceLineNo">164</span> * more efficient to close scanners which are not needed than keep them in<a name="line.164"></a> |
| <span class="sourceLineNo">165</span> * the heap. This is also required for certain optimizations.<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> if (pee == null || !moreCells) {<a name="line.168"></a> |
| <span class="sourceLineNo">169</span> // add the scanner that is to be closed<a name="line.169"></a> |
| <span class="sourceLineNo">170</span> this.scannersForDelayedClose.add(this.current);<a name="line.170"></a> |
| <span class="sourceLineNo">171</span> } else {<a name="line.171"></a> |
| <span class="sourceLineNo">172</span> this.heap.add(this.current);<a name="line.172"></a> |
| <span class="sourceLineNo">173</span> }<a name="line.173"></a> |
| <span class="sourceLineNo">174</span> this.current = null;<a name="line.174"></a> |
| <span class="sourceLineNo">175</span> this.current = pollRealKV();<a name="line.175"></a> |
| <span class="sourceLineNo">176</span> if (this.current == null) {<a name="line.176"></a> |
| <span class="sourceLineNo">177</span> moreCells = scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.177"></a> |
| <span class="sourceLineNo">178</span> }<a name="line.178"></a> |
| <span class="sourceLineNo">179</span> return moreCells;<a name="line.179"></a> |
| <span class="sourceLineNo">180</span> }<a name="line.180"></a> |
| <span class="sourceLineNo">181</span><a name="line.181"></a> |
| <span class="sourceLineNo">182</span> protected static class KVScannerComparator implements Comparator<KeyValueScanner> {<a name="line.182"></a> |
| <span class="sourceLineNo">183</span> protected CellComparator kvComparator;<a name="line.183"></a> |
| <span class="sourceLineNo">184</span> /**<a name="line.184"></a> |
| <span class="sourceLineNo">185</span> * Constructor<a name="line.185"></a> |
| <span class="sourceLineNo">186</span> * @param kvComparator<a name="line.186"></a> |
| <span class="sourceLineNo">187</span> */<a name="line.187"></a> |
| <span class="sourceLineNo">188</span> public KVScannerComparator(CellComparator kvComparator) {<a name="line.188"></a> |
| <span class="sourceLineNo">189</span> this.kvComparator = kvComparator;<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> @Override<a name="line.192"></a> |
| <span class="sourceLineNo">193</span> public int compare(KeyValueScanner left, KeyValueScanner right) {<a name="line.193"></a> |
| <span class="sourceLineNo">194</span> int comparison = compare(left.peek(), right.peek());<a name="line.194"></a> |
| <span class="sourceLineNo">195</span> if (comparison != 0) {<a name="line.195"></a> |
| <span class="sourceLineNo">196</span> return comparison;<a name="line.196"></a> |
| <span class="sourceLineNo">197</span> } else {<a name="line.197"></a> |
| <span class="sourceLineNo">198</span> // Since both the keys are exactly the same, we break the tie in favor of higher ordered<a name="line.198"></a> |
| <span class="sourceLineNo">199</span> // scanner since it'll have newer data. Since higher value should come first, we reverse<a name="line.199"></a> |
| <span class="sourceLineNo">200</span> // sort here.<a name="line.200"></a> |
| <span class="sourceLineNo">201</span> return Long.compare(right.getScannerOrder(), left.getScannerOrder());<a name="line.201"></a> |
| <span class="sourceLineNo">202</span> }<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> * Compares two KeyValue<a name="line.205"></a> |
| <span class="sourceLineNo">206</span> * @param left<a name="line.206"></a> |
| <span class="sourceLineNo">207</span> * @param right<a name="line.207"></a> |
| <span class="sourceLineNo">208</span> * @return less than 0 if left is smaller, 0 if equal etc..<a name="line.208"></a> |
| <span class="sourceLineNo">209</span> */<a name="line.209"></a> |
| <span class="sourceLineNo">210</span> public int compare(Cell left, Cell right) {<a name="line.210"></a> |
| <span class="sourceLineNo">211</span> return this.kvComparator.compare(left, right);<a name="line.211"></a> |
| <span class="sourceLineNo">212</span> }<a name="line.212"></a> |
| <span class="sourceLineNo">213</span> /**<a name="line.213"></a> |
| <span class="sourceLineNo">214</span> * @return KVComparator<a name="line.214"></a> |
| <span class="sourceLineNo">215</span> */<a name="line.215"></a> |
| <span class="sourceLineNo">216</span> public CellComparator getComparator() {<a name="line.216"></a> |
| <span class="sourceLineNo">217</span> return this.kvComparator;<a name="line.217"></a> |
| <span class="sourceLineNo">218</span> }<a name="line.218"></a> |
| <span class="sourceLineNo">219</span> }<a name="line.219"></a> |
| <span class="sourceLineNo">220</span><a name="line.220"></a> |
| <span class="sourceLineNo">221</span> @Override<a name="line.221"></a> |
| <span class="sourceLineNo">222</span> public void close() {<a name="line.222"></a> |
| <span class="sourceLineNo">223</span> for (KeyValueScanner scanner : this.scannersForDelayedClose) {<a name="line.223"></a> |
| <span class="sourceLineNo">224</span> scanner.close();<a name="line.224"></a> |
| <span class="sourceLineNo">225</span> }<a name="line.225"></a> |
| <span class="sourceLineNo">226</span> this.scannersForDelayedClose.clear();<a name="line.226"></a> |
| <span class="sourceLineNo">227</span> if (this.current != null) {<a name="line.227"></a> |
| <span class="sourceLineNo">228</span> this.current.close();<a name="line.228"></a> |
| <span class="sourceLineNo">229</span> }<a name="line.229"></a> |
| <span class="sourceLineNo">230</span> if (this.heap != null) {<a name="line.230"></a> |
| <span class="sourceLineNo">231</span> // Order of closing the scanners shouldn't matter here, so simply iterate and close them.<a name="line.231"></a> |
| <span class="sourceLineNo">232</span> for (KeyValueScanner scanner : heap) {<a name="line.232"></a> |
| <span class="sourceLineNo">233</span> scanner.close();<a name="line.233"></a> |
| <span class="sourceLineNo">234</span> }<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><a name="line.237"></a> |
| <span class="sourceLineNo">238</span> /**<a name="line.238"></a> |
| <span class="sourceLineNo">239</span> * Seeks all scanners at or below the specified seek key. If we earlied-out<a name="line.239"></a> |
| <span class="sourceLineNo">240</span> * of a row, we may end up skipping values that were never reached yet.<a name="line.240"></a> |
| <span class="sourceLineNo">241</span> * Rather than iterating down, we want to give the opportunity to re-seek.<a name="line.241"></a> |
| <span class="sourceLineNo">242</span> * <p><a name="line.242"></a> |
| <span class="sourceLineNo">243</span> * As individual scanners may run past their ends, those scanners are<a name="line.243"></a> |
| <span class="sourceLineNo">244</span> * automatically closed and removed from the heap.<a name="line.244"></a> |
| <span class="sourceLineNo">245</span> * <p><a name="line.245"></a> |
| <span class="sourceLineNo">246</span> * This function (and {@link #reseek(Cell)}) does not do multi-column<a name="line.246"></a> |
| <span class="sourceLineNo">247</span> * Bloom filter and lazy-seek optimizations. To enable those, call<a name="line.247"></a> |
| <span class="sourceLineNo">248</span> * {@link #requestSeek(Cell, boolean, boolean)}.<a name="line.248"></a> |
| <span class="sourceLineNo">249</span> * @param seekKey KeyValue to seek at or after<a name="line.249"></a> |
| <span class="sourceLineNo">250</span> * @return true if KeyValues exist at or after specified key, false if not<a name="line.250"></a> |
| <span class="sourceLineNo">251</span> * @throws IOException<a name="line.251"></a> |
| <span class="sourceLineNo">252</span> */<a name="line.252"></a> |
| <span class="sourceLineNo">253</span> @Override<a name="line.253"></a> |
| <span class="sourceLineNo">254</span> public boolean seek(Cell seekKey) throws IOException {<a name="line.254"></a> |
| <span class="sourceLineNo">255</span> return generalizedSeek(false, // This is not a lazy seek<a name="line.255"></a> |
| <span class="sourceLineNo">256</span> seekKey,<a name="line.256"></a> |
| <span class="sourceLineNo">257</span> false, // forward (false: this is not a reseek)<a name="line.257"></a> |
| <span class="sourceLineNo">258</span> false); // Not using Bloom filters<a name="line.258"></a> |
| <span class="sourceLineNo">259</span> }<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> * This function is identical to the {@link #seek(Cell)} function except<a name="line.262"></a> |
| <span class="sourceLineNo">263</span> * that scanner.seek(seekKey) is changed to scanner.reseek(seekKey).<a name="line.263"></a> |
| <span class="sourceLineNo">264</span> */<a name="line.264"></a> |
| <span class="sourceLineNo">265</span> @Override<a name="line.265"></a> |
| <span class="sourceLineNo">266</span> public boolean reseek(Cell seekKey) throws IOException {<a name="line.266"></a> |
| <span class="sourceLineNo">267</span> return generalizedSeek(false, // This is not a lazy seek<a name="line.267"></a> |
| <span class="sourceLineNo">268</span> seekKey,<a name="line.268"></a> |
| <span class="sourceLineNo">269</span> true, // forward (true because this is reseek)<a name="line.269"></a> |
| <span class="sourceLineNo">270</span> false); // Not using Bloom filters<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> * {@inheritDoc}<a name="line.274"></a> |
| <span class="sourceLineNo">275</span> */<a name="line.275"></a> |
| <span class="sourceLineNo">276</span> @Override<a name="line.276"></a> |
| <span class="sourceLineNo">277</span> public boolean requestSeek(Cell key, boolean forward,<a name="line.277"></a> |
| <span class="sourceLineNo">278</span> boolean useBloom) throws IOException {<a name="line.278"></a> |
| <span class="sourceLineNo">279</span> return generalizedSeek(true, key, forward, useBloom);<a name="line.279"></a> |
| <span class="sourceLineNo">280</span> }<a name="line.280"></a> |
| <span class="sourceLineNo">281</span><a name="line.281"></a> |
| <span class="sourceLineNo">282</span> /**<a name="line.282"></a> |
| <span class="sourceLineNo">283</span> * @param isLazy whether we are trying to seek to exactly the given row/col.<a name="line.283"></a> |
| <span class="sourceLineNo">284</span> * Enables Bloom filter and most-recent-file-first optimizations for<a name="line.284"></a> |
| <span class="sourceLineNo">285</span> * multi-column get/scan queries.<a name="line.285"></a> |
| <span class="sourceLineNo">286</span> * @param seekKey key to seek to<a name="line.286"></a> |
| <span class="sourceLineNo">287</span> * @param forward whether to seek forward (also known as reseek)<a name="line.287"></a> |
| <span class="sourceLineNo">288</span> * @param useBloom whether to optimize seeks using Bloom filters<a name="line.288"></a> |
| <span class="sourceLineNo">289</span> */<a name="line.289"></a> |
| <span class="sourceLineNo">290</span> private boolean generalizedSeek(boolean isLazy, Cell seekKey,<a name="line.290"></a> |
| <span class="sourceLineNo">291</span> boolean forward, boolean useBloom) throws IOException {<a name="line.291"></a> |
| <span class="sourceLineNo">292</span> if (!isLazy && useBloom) {<a name="line.292"></a> |
| <span class="sourceLineNo">293</span> throw new IllegalArgumentException("Multi-column Bloom filter " +<a name="line.293"></a> |
| <span class="sourceLineNo">294</span> "optimization requires a lazy seek");<a name="line.294"></a> |
| <span class="sourceLineNo">295</span> }<a name="line.295"></a> |
| <span class="sourceLineNo">296</span><a name="line.296"></a> |
| <span class="sourceLineNo">297</span> if (current == null) {<a name="line.297"></a> |
| <span class="sourceLineNo">298</span> return false;<a name="line.298"></a> |
| <span class="sourceLineNo">299</span> }<a name="line.299"></a> |
| <span class="sourceLineNo">300</span><a name="line.300"></a> |
| <span class="sourceLineNo">301</span> KeyValueScanner scanner = current;<a name="line.301"></a> |
| <span class="sourceLineNo">302</span> try {<a name="line.302"></a> |
| <span class="sourceLineNo">303</span> while (scanner != null) {<a name="line.303"></a> |
| <span class="sourceLineNo">304</span> Cell topKey = scanner.peek();<a name="line.304"></a> |
| <span class="sourceLineNo">305</span> if (comparator.getComparator().compare(seekKey, topKey) <= 0) {<a name="line.305"></a> |
| <span class="sourceLineNo">306</span> // Top KeyValue is at-or-after Seek KeyValue. We only know that all<a name="line.306"></a> |
| <span class="sourceLineNo">307</span> // scanners are at or after seekKey (because fake keys of<a name="line.307"></a> |
| <span class="sourceLineNo">308</span> // scanners where a lazy-seek operation has been done are not greater<a name="line.308"></a> |
| <span class="sourceLineNo">309</span> // than their real next keys) but we still need to enforce our<a name="line.309"></a> |
| <span class="sourceLineNo">310</span> // invariant that the top scanner has done a real seek. This way<a name="line.310"></a> |
| <span class="sourceLineNo">311</span> // StoreScanner and RegionScanner do not have to worry about fake<a name="line.311"></a> |
| <span class="sourceLineNo">312</span> // keys.<a name="line.312"></a> |
| <span class="sourceLineNo">313</span> heap.add(scanner);<a name="line.313"></a> |
| <span class="sourceLineNo">314</span> scanner = null;<a name="line.314"></a> |
| <span class="sourceLineNo">315</span> current = pollRealKV();<a name="line.315"></a> |
| <span class="sourceLineNo">316</span> return current != null;<a name="line.316"></a> |
| <span class="sourceLineNo">317</span> }<a name="line.317"></a> |
| <span class="sourceLineNo">318</span><a name="line.318"></a> |
| <span class="sourceLineNo">319</span> boolean seekResult;<a name="line.319"></a> |
| <span class="sourceLineNo">320</span> if (isLazy && heap.size() > 0) {<a name="line.320"></a> |
| <span class="sourceLineNo">321</span> // If there is only one scanner left, we don't do lazy seek.<a name="line.321"></a> |
| <span class="sourceLineNo">322</span> seekResult = scanner.requestSeek(seekKey, forward, useBloom);<a name="line.322"></a> |
| <span class="sourceLineNo">323</span> } else {<a name="line.323"></a> |
| <span class="sourceLineNo">324</span> seekResult = NonLazyKeyValueScanner.doRealSeek(scanner, seekKey,<a name="line.324"></a> |
| <span class="sourceLineNo">325</span> forward);<a name="line.325"></a> |
| <span class="sourceLineNo">326</span> }<a name="line.326"></a> |
| <span class="sourceLineNo">327</span><a name="line.327"></a> |
| <span class="sourceLineNo">328</span> if (!seekResult) {<a name="line.328"></a> |
| <span class="sourceLineNo">329</span> this.scannersForDelayedClose.add(scanner);<a name="line.329"></a> |
| <span class="sourceLineNo">330</span> } else {<a name="line.330"></a> |
| <span class="sourceLineNo">331</span> heap.add(scanner);<a name="line.331"></a> |
| <span class="sourceLineNo">332</span> }<a name="line.332"></a> |
| <span class="sourceLineNo">333</span> scanner = heap.poll();<a name="line.333"></a> |
| <span class="sourceLineNo">334</span> if (scanner == null) {<a name="line.334"></a> |
| <span class="sourceLineNo">335</span> current = null;<a name="line.335"></a> |
| <span class="sourceLineNo">336</span> }<a name="line.336"></a> |
| <span class="sourceLineNo">337</span> }<a name="line.337"></a> |
| <span class="sourceLineNo">338</span> } catch (Exception e) {<a name="line.338"></a> |
| <span class="sourceLineNo">339</span> if (scanner != null) {<a name="line.339"></a> |
| <span class="sourceLineNo">340</span> try {<a name="line.340"></a> |
| <span class="sourceLineNo">341</span> scanner.close();<a name="line.341"></a> |
| <span class="sourceLineNo">342</span> } catch (Exception ce) {<a name="line.342"></a> |
| <span class="sourceLineNo">343</span> LOG.warn("close KeyValueScanner error", ce);<a name="line.343"></a> |
| <span class="sourceLineNo">344</span> }<a name="line.344"></a> |
| <span class="sourceLineNo">345</span> }<a name="line.345"></a> |
| <span class="sourceLineNo">346</span> throw e;<a name="line.346"></a> |
| <span class="sourceLineNo">347</span> }<a name="line.347"></a> |
| <span class="sourceLineNo">348</span><a name="line.348"></a> |
| <span class="sourceLineNo">349</span> // Heap is returning empty, scanner is done<a name="line.349"></a> |
| <span class="sourceLineNo">350</span> return false;<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> /**<a name="line.353"></a> |
| <span class="sourceLineNo">354</span> * Fetches the top sub-scanner from the priority queue, ensuring that a real<a name="line.354"></a> |
| <span class="sourceLineNo">355</span> * seek has been done on it. Works by fetching the top sub-scanner, and if it<a name="line.355"></a> |
| <span class="sourceLineNo">356</span> * has not done a real seek, making it do so (which will modify its top KV),<a name="line.356"></a> |
| <span class="sourceLineNo">357</span> * putting it back, and repeating this until success. Relies on the fact that<a name="line.357"></a> |
| <span class="sourceLineNo">358</span> * on a lazy seek we set the current key of a StoreFileScanner to a KV that<a name="line.358"></a> |
| <span class="sourceLineNo">359</span> * is not greater than the real next KV to be read from that file, so the<a name="line.359"></a> |
| <span class="sourceLineNo">360</span> * scanner that bubbles up to the top of the heap will have global next KV in<a name="line.360"></a> |
| <span class="sourceLineNo">361</span> * this scanner heap if (1) it has done a real seek and (2) its KV is the top<a name="line.361"></a> |
| <span class="sourceLineNo">362</span> * among all top KVs (some of which are fake) in the scanner heap.<a name="line.362"></a> |
| <span class="sourceLineNo">363</span> */<a name="line.363"></a> |
| <span class="sourceLineNo">364</span> protected KeyValueScanner pollRealKV() throws IOException {<a name="line.364"></a> |
| <span class="sourceLineNo">365</span> KeyValueScanner kvScanner = heap.poll();<a name="line.365"></a> |
| <span class="sourceLineNo">366</span> if (kvScanner == null) {<a name="line.366"></a> |
| <span class="sourceLineNo">367</span> return null;<a name="line.367"></a> |
| <span class="sourceLineNo">368</span> }<a name="line.368"></a> |
| <span class="sourceLineNo">369</span><a name="line.369"></a> |
| <span class="sourceLineNo">370</span> while (kvScanner != null && !kvScanner.realSeekDone()) {<a name="line.370"></a> |
| <span class="sourceLineNo">371</span> if (kvScanner.peek() != null) {<a name="line.371"></a> |
| <span class="sourceLineNo">372</span> try {<a name="line.372"></a> |
| <span class="sourceLineNo">373</span> kvScanner.enforceSeek();<a name="line.373"></a> |
| <span class="sourceLineNo">374</span> } catch (IOException ioe) {<a name="line.374"></a> |
| <span class="sourceLineNo">375</span> // Add the item to delayed close set in case it is leak from close<a name="line.375"></a> |
| <span class="sourceLineNo">376</span> this.scannersForDelayedClose.add(kvScanner);<a name="line.376"></a> |
| <span class="sourceLineNo">377</span> throw ioe;<a name="line.377"></a> |
| <span class="sourceLineNo">378</span> }<a name="line.378"></a> |
| <span class="sourceLineNo">379</span> Cell curKV = kvScanner.peek();<a name="line.379"></a> |
| <span class="sourceLineNo">380</span> if (curKV != null) {<a name="line.380"></a> |
| <span class="sourceLineNo">381</span> KeyValueScanner nextEarliestScanner = heap.peek();<a name="line.381"></a> |
| <span class="sourceLineNo">382</span> if (nextEarliestScanner == null) {<a name="line.382"></a> |
| <span class="sourceLineNo">383</span> // The heap is empty. Return the only possible scanner.<a name="line.383"></a> |
| <span class="sourceLineNo">384</span> return kvScanner;<a name="line.384"></a> |
| <span class="sourceLineNo">385</span> }<a name="line.385"></a> |
| <span class="sourceLineNo">386</span><a name="line.386"></a> |
| <span class="sourceLineNo">387</span> // Compare the current scanner to the next scanner. We try to avoid<a name="line.387"></a> |
| <span class="sourceLineNo">388</span> // putting the current one back into the heap if possible.<a name="line.388"></a> |
| <span class="sourceLineNo">389</span> Cell nextKV = nextEarliestScanner.peek();<a name="line.389"></a> |
| <span class="sourceLineNo">390</span> if (nextKV == null || comparator.compare(curKV, nextKV) < 0) {<a name="line.390"></a> |
| <span class="sourceLineNo">391</span> // We already have the scanner with the earliest KV, so return it.<a name="line.391"></a> |
| <span class="sourceLineNo">392</span> return kvScanner;<a name="line.392"></a> |
| <span class="sourceLineNo">393</span> }<a name="line.393"></a> |
| <span class="sourceLineNo">394</span><a name="line.394"></a> |
| <span class="sourceLineNo">395</span> // Otherwise, put the scanner back into the heap and let it compete<a name="line.395"></a> |
| <span class="sourceLineNo">396</span> // against all other scanners (both those that have done a "real<a name="line.396"></a> |
| <span class="sourceLineNo">397</span> // seek" and a "lazy seek").<a name="line.397"></a> |
| <span class="sourceLineNo">398</span> heap.add(kvScanner);<a name="line.398"></a> |
| <span class="sourceLineNo">399</span> } else {<a name="line.399"></a> |
| <span class="sourceLineNo">400</span> // Close the scanner because we did a real seek and found out there<a name="line.400"></a> |
| <span class="sourceLineNo">401</span> // are no more KVs.<a name="line.401"></a> |
| <span class="sourceLineNo">402</span> this.scannersForDelayedClose.add(kvScanner);<a name="line.402"></a> |
| <span class="sourceLineNo">403</span> }<a name="line.403"></a> |
| <span class="sourceLineNo">404</span> } else {<a name="line.404"></a> |
| <span class="sourceLineNo">405</span> // Close the scanner because it has already run out of KVs even before<a name="line.405"></a> |
| <span class="sourceLineNo">406</span> // we had to do a real seek on it.<a name="line.406"></a> |
| <span class="sourceLineNo">407</span> this.scannersForDelayedClose.add(kvScanner);<a name="line.407"></a> |
| <span class="sourceLineNo">408</span> }<a name="line.408"></a> |
| <span class="sourceLineNo">409</span> kvScanner = heap.poll();<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> return kvScanner;<a name="line.412"></a> |
| <span class="sourceLineNo">413</span> }<a name="line.413"></a> |
| <span class="sourceLineNo">414</span><a name="line.414"></a> |
| <span class="sourceLineNo">415</span> /**<a name="line.415"></a> |
| <span class="sourceLineNo">416</span> * @return the current Heap<a name="line.416"></a> |
| <span class="sourceLineNo">417</span> */<a name="line.417"></a> |
| <span class="sourceLineNo">418</span> public PriorityQueue<KeyValueScanner> getHeap() {<a name="line.418"></a> |
| <span class="sourceLineNo">419</span> return this.heap;<a name="line.419"></a> |
| <span class="sourceLineNo">420</span> }<a name="line.420"></a> |
| <span class="sourceLineNo">421</span><a name="line.421"></a> |
| <span class="sourceLineNo">422</span><a name="line.422"></a> |
| <span class="sourceLineNo">423</span> @VisibleForTesting<a name="line.423"></a> |
| <span class="sourceLineNo">424</span> KeyValueScanner getCurrentForTesting() {<a name="line.424"></a> |
| <span class="sourceLineNo">425</span> return current;<a name="line.425"></a> |
| <span class="sourceLineNo">426</span> }<a name="line.426"></a> |
| <span class="sourceLineNo">427</span><a name="line.427"></a> |
| <span class="sourceLineNo">428</span> @Override<a name="line.428"></a> |
| <span class="sourceLineNo">429</span> public Cell getNextIndexedKey() {<a name="line.429"></a> |
| <span class="sourceLineNo">430</span> // here we return the next index key from the top scanner<a name="line.430"></a> |
| <span class="sourceLineNo">431</span> return current == null ? null : current.getNextIndexedKey();<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> @Override<a name="line.434"></a> |
| <span class="sourceLineNo">435</span> public void shipped() throws IOException {<a name="line.435"></a> |
| <span class="sourceLineNo">436</span> for (KeyValueScanner scanner : this.scannersForDelayedClose) {<a name="line.436"></a> |
| <span class="sourceLineNo">437</span> scanner.close(); // There wont be further fetch of Cells from these scanners. Just close.<a name="line.437"></a> |
| <span class="sourceLineNo">438</span> }<a name="line.438"></a> |
| <span class="sourceLineNo">439</span> this.scannersForDelayedClose.clear();<a name="line.439"></a> |
| <span class="sourceLineNo">440</span> if (this.current != null) {<a name="line.440"></a> |
| <span class="sourceLineNo">441</span> this.current.shipped();<a name="line.441"></a> |
| <span class="sourceLineNo">442</span> }<a name="line.442"></a> |
| <span class="sourceLineNo">443</span> if (this.heap != null) {<a name="line.443"></a> |
| <span class="sourceLineNo">444</span> for (KeyValueScanner scanner : this.heap) {<a name="line.444"></a> |
| <span class="sourceLineNo">445</span> scanner.shipped();<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> }<a name="line.448"></a> |
| <span class="sourceLineNo">449</span>}<a name="line.449"></a> |
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| </html> |
