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Posted to commits@hbase.apache.org by mi...@apache.org on 2015/12/16 17:51:13 UTC
[28/51] [partial] hbase-site git commit: Published site at
60d33ce34191533bb858852584bd9bddfeb16a23.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/539ad177/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/CacheStats.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/CacheStats.html b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/CacheStats.html
index 09ac1a3..ac458a0 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/CacheStats.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/CacheStats.html
@@ -30,273 +30,275 @@
<span class="sourceLineNo">022</span><a name="line.22"></a>
<span class="sourceLineNo">023</span>import org.apache.hadoop.hbase.classification.InterfaceAudience;<a name="line.23"></a>
<span class="sourceLineNo">024</span><a name="line.24"></a>
-<span class="sourceLineNo">025</span>import com.yammer.metrics.core.Histogram;<a name="line.25"></a>
-<span class="sourceLineNo">026</span>import com.yammer.metrics.core.MetricsRegistry;<a name="line.26"></a>
+<span class="sourceLineNo">025</span>import com.codahale.metrics.Histogram;<a name="line.25"></a>
+<span class="sourceLineNo">026</span>import com.codahale.metrics.MetricRegistry;<a name="line.26"></a>
<span class="sourceLineNo">027</span><a name="line.27"></a>
-<span class="sourceLineNo">028</span>/**<a name="line.28"></a>
-<span class="sourceLineNo">029</span> * Class that implements cache metrics.<a name="line.29"></a>
-<span class="sourceLineNo">030</span> */<a name="line.30"></a>
-<span class="sourceLineNo">031</span>@InterfaceAudience.Private<a name="line.31"></a>
-<span class="sourceLineNo">032</span>public class CacheStats {<a name="line.32"></a>
-<span class="sourceLineNo">033</span> /**<a name="line.33"></a>
-<span class="sourceLineNo">034</span> * Needed making histograms.<a name="line.34"></a>
-<span class="sourceLineNo">035</span> */<a name="line.35"></a>
-<span class="sourceLineNo">036</span> private static final MetricsRegistry METRICS = new MetricsRegistry();<a name="line.36"></a>
-<span class="sourceLineNo">037</span><a name="line.37"></a>
-<span class="sourceLineNo">038</span> /** Sliding window statistics. The number of metric periods to include in<a name="line.38"></a>
-<span class="sourceLineNo">039</span> * sliding window hit ratio calculations.<a name="line.39"></a>
-<span class="sourceLineNo">040</span> */<a name="line.40"></a>
-<span class="sourceLineNo">041</span> static final int DEFAULT_WINDOW_PERIODS = 5;<a name="line.41"></a>
-<span class="sourceLineNo">042</span><a name="line.42"></a>
-<span class="sourceLineNo">043</span> /** The number of getBlock requests that were cache hits */<a name="line.43"></a>
-<span class="sourceLineNo">044</span> private final AtomicLong hitCount = new AtomicLong(0);<a name="line.44"></a>
-<span class="sourceLineNo">045</span><a name="line.45"></a>
-<span class="sourceLineNo">046</span> /** The number of getBlock requests that were cache hits from primary replica */<a name="line.46"></a>
-<span class="sourceLineNo">047</span> private final AtomicLong primaryHitCount = new AtomicLong(0);<a name="line.47"></a>
-<span class="sourceLineNo">048</span> <a name="line.48"></a>
-<span class="sourceLineNo">049</span> /**<a name="line.49"></a>
-<span class="sourceLineNo">050</span> * The number of getBlock requests that were cache hits, but only from<a name="line.50"></a>
-<span class="sourceLineNo">051</span> * requests that were set to use the block cache. This is because all reads<a name="line.51"></a>
-<span class="sourceLineNo">052</span> * attempt to read from the block cache even if they will not put new blocks<a name="line.52"></a>
-<span class="sourceLineNo">053</span> * into the block cache. See HBASE-2253 for more information.<a name="line.53"></a>
-<span class="sourceLineNo">054</span> */<a name="line.54"></a>
-<span class="sourceLineNo">055</span> private final AtomicLong hitCachingCount = new AtomicLong(0);<a name="line.55"></a>
-<span class="sourceLineNo">056</span><a name="line.56"></a>
-<span class="sourceLineNo">057</span> /** The number of getBlock requests that were cache misses */<a name="line.57"></a>
-<span class="sourceLineNo">058</span> private final AtomicLong missCount = new AtomicLong(0);<a name="line.58"></a>
-<span class="sourceLineNo">059</span><a name="line.59"></a>
-<span class="sourceLineNo">060</span> /** The number of getBlock requests for primary replica that were cache misses */<a name="line.60"></a>
-<span class="sourceLineNo">061</span> private final AtomicLong primaryMissCount = new AtomicLong(0);<a name="line.61"></a>
-<span class="sourceLineNo">062</span> /**<a name="line.62"></a>
-<span class="sourceLineNo">063</span> * The number of getBlock requests that were cache misses, but only from<a name="line.63"></a>
-<span class="sourceLineNo">064</span> * requests that were set to use the block cache.<a name="line.64"></a>
-<span class="sourceLineNo">065</span> */<a name="line.65"></a>
-<span class="sourceLineNo">066</span> private final AtomicLong missCachingCount = new AtomicLong(0);<a name="line.66"></a>
-<span class="sourceLineNo">067</span><a name="line.67"></a>
-<span class="sourceLineNo">068</span> /** The number of times an eviction has occurred */<a name="line.68"></a>
-<span class="sourceLineNo">069</span> private final AtomicLong evictionCount = new AtomicLong(0);<a name="line.69"></a>
-<span class="sourceLineNo">070</span><a name="line.70"></a>
-<span class="sourceLineNo">071</span> /** The total number of blocks that have been evicted */<a name="line.71"></a>
-<span class="sourceLineNo">072</span> private final AtomicLong evictedBlockCount = new AtomicLong(0);<a name="line.72"></a>
-<span class="sourceLineNo">073</span><a name="line.73"></a>
-<span class="sourceLineNo">074</span> /** The total number of blocks for primary replica that have been evicted */<a name="line.74"></a>
-<span class="sourceLineNo">075</span> private final AtomicLong primaryEvictedBlockCount = new AtomicLong(0);<a name="line.75"></a>
-<span class="sourceLineNo">076</span><a name="line.76"></a>
-<span class="sourceLineNo">077</span> /** The total number of blocks that were not inserted. */<a name="line.77"></a>
-<span class="sourceLineNo">078</span> private final AtomicLong failedInserts = new AtomicLong(0);<a name="line.78"></a>
-<span class="sourceLineNo">079</span><a name="line.79"></a>
-<span class="sourceLineNo">080</span> /** The number of metrics periods to include in window */<a name="line.80"></a>
-<span class="sourceLineNo">081</span> private final int numPeriodsInWindow;<a name="line.81"></a>
-<span class="sourceLineNo">082</span> /** Hit counts for each period in window */<a name="line.82"></a>
-<span class="sourceLineNo">083</span> private final long [] hitCounts;<a name="line.83"></a>
-<span class="sourceLineNo">084</span> /** Caching hit counts for each period in window */<a name="line.84"></a>
-<span class="sourceLineNo">085</span> private final long [] hitCachingCounts;<a name="line.85"></a>
-<span class="sourceLineNo">086</span> /** Access counts for each period in window */<a name="line.86"></a>
-<span class="sourceLineNo">087</span> private final long [] requestCounts;<a name="line.87"></a>
-<span class="sourceLineNo">088</span> /** Caching access counts for each period in window */<a name="line.88"></a>
-<span class="sourceLineNo">089</span> private final long [] requestCachingCounts;<a name="line.89"></a>
-<span class="sourceLineNo">090</span> /** Last hit count read */<a name="line.90"></a>
-<span class="sourceLineNo">091</span> private long lastHitCount = 0;<a name="line.91"></a>
-<span class="sourceLineNo">092</span> /** Last hit caching count read */<a name="line.92"></a>
-<span class="sourceLineNo">093</span> private long lastHitCachingCount = 0;<a name="line.93"></a>
-<span class="sourceLineNo">094</span> /** Last request count read */<a name="line.94"></a>
-<span class="sourceLineNo">095</span> private long lastRequestCount = 0;<a name="line.95"></a>
-<span class="sourceLineNo">096</span> /** Last request caching count read */<a name="line.96"></a>
-<span class="sourceLineNo">097</span> private long lastRequestCachingCount = 0;<a name="line.97"></a>
-<span class="sourceLineNo">098</span> /** Current window index (next to be updated) */<a name="line.98"></a>
-<span class="sourceLineNo">099</span> private int windowIndex = 0;<a name="line.99"></a>
-<span class="sourceLineNo">100</span> /**<a name="line.100"></a>
-<span class="sourceLineNo">101</span> * Keep running age at eviction time<a name="line.101"></a>
-<span class="sourceLineNo">102</span> */<a name="line.102"></a>
-<span class="sourceLineNo">103</span> private Histogram ageAtEviction;<a name="line.103"></a>
-<span class="sourceLineNo">104</span> private long startTime = System.nanoTime();<a name="line.104"></a>
-<span class="sourceLineNo">105</span><a name="line.105"></a>
-<span class="sourceLineNo">106</span> public CacheStats(final String name) {<a name="line.106"></a>
-<span class="sourceLineNo">107</span> this(name, DEFAULT_WINDOW_PERIODS);<a name="line.107"></a>
-<span class="sourceLineNo">108</span> }<a name="line.108"></a>
-<span class="sourceLineNo">109</span><a name="line.109"></a>
-<span class="sourceLineNo">110</span> public CacheStats(final String name, int numPeriodsInWindow) {<a name="line.110"></a>
-<span class="sourceLineNo">111</span> this.numPeriodsInWindow = numPeriodsInWindow;<a name="line.111"></a>
-<span class="sourceLineNo">112</span> this.hitCounts = initializeZeros(numPeriodsInWindow);<a name="line.112"></a>
-<span class="sourceLineNo">113</span> this.hitCachingCounts = initializeZeros(numPeriodsInWindow);<a name="line.113"></a>
-<span class="sourceLineNo">114</span> this.requestCounts = initializeZeros(numPeriodsInWindow);<a name="line.114"></a>
-<span class="sourceLineNo">115</span> this.requestCachingCounts = initializeZeros(numPeriodsInWindow);<a name="line.115"></a>
-<span class="sourceLineNo">116</span> this.ageAtEviction = METRICS.newHistogram(CacheStats.class, name + ".ageAtEviction");<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 String toString() {<a name="line.120"></a>
-<span class="sourceLineNo">121</span> AgeSnapshot snapshot = getAgeAtEvictionSnapshot();<a name="line.121"></a>
-<span class="sourceLineNo">122</span> return "hitCount=" + getHitCount() + ", hitCachingCount=" + getHitCachingCount() +<a name="line.122"></a>
-<span class="sourceLineNo">123</span> ", missCount=" + getMissCount() + ", missCachingCount=" + getMissCachingCount() +<a name="line.123"></a>
-<span class="sourceLineNo">124</span> ", evictionCount=" + getEvictionCount() +<a name="line.124"></a>
-<span class="sourceLineNo">125</span> ", evictedBlockCount=" + getEvictedCount() +<a name="line.125"></a>
-<span class="sourceLineNo">126</span> ", primaryMissCount=" + getPrimaryMissCount() +<a name="line.126"></a>
-<span class="sourceLineNo">127</span> ", primaryHitCount=" + getPrimaryHitCount() +<a name="line.127"></a>
-<span class="sourceLineNo">128</span> ", evictedAgeMean=" + snapshot.getMean() +<a name="line.128"></a>
-<span class="sourceLineNo">129</span> ", evictedAgeStdDev=" + snapshot.getStdDev();<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> public void miss(boolean caching, boolean primary) {<a name="line.132"></a>
-<span class="sourceLineNo">133</span> missCount.incrementAndGet();<a name="line.133"></a>
-<span class="sourceLineNo">134</span> if (primary) primaryMissCount.incrementAndGet();<a name="line.134"></a>
-<span class="sourceLineNo">135</span> if (caching) missCachingCount.incrementAndGet();<a name="line.135"></a>
-<span class="sourceLineNo">136</span> }<a name="line.136"></a>
-<span class="sourceLineNo">137</span><a name="line.137"></a>
-<span class="sourceLineNo">138</span> public void hit(boolean caching) {<a name="line.138"></a>
-<span class="sourceLineNo">139</span> hit(caching, true);<a name="line.139"></a>
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-<span class="sourceLineNo">141</span><a name="line.141"></a>
-<span class="sourceLineNo">142</span> public void hit(boolean caching, boolean primary) {<a name="line.142"></a>
-<span class="sourceLineNo">143</span> hitCount.incrementAndGet();<a name="line.143"></a>
-<span class="sourceLineNo">144</span> if (primary) primaryHitCount.incrementAndGet();<a name="line.144"></a>
-<span class="sourceLineNo">145</span> if (caching) hitCachingCount.incrementAndGet();<a name="line.145"></a>
-<span class="sourceLineNo">146</span> }<a name="line.146"></a>
-<span class="sourceLineNo">147</span><a name="line.147"></a>
-<span class="sourceLineNo">148</span> public void evict() {<a name="line.148"></a>
-<span class="sourceLineNo">149</span> evictionCount.incrementAndGet();<a name="line.149"></a>
-<span class="sourceLineNo">150</span> }<a name="line.150"></a>
-<span class="sourceLineNo">151</span><a name="line.151"></a>
-<span class="sourceLineNo">152</span> public void evicted(final long t, boolean primary) {<a name="line.152"></a>
-<span class="sourceLineNo">153</span> if (t > this.startTime) this.ageAtEviction.update(t - this.startTime);<a name="line.153"></a>
-<span class="sourceLineNo">154</span> this.evictedBlockCount.incrementAndGet();<a name="line.154"></a>
-<span class="sourceLineNo">155</span> if (primary) {<a name="line.155"></a>
-<span class="sourceLineNo">156</span> primaryEvictedBlockCount.incrementAndGet();<a name="line.156"></a>
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-<span class="sourceLineNo">159</span><a name="line.159"></a>
-<span class="sourceLineNo">160</span> public long failInsert() {<a name="line.160"></a>
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-<span class="sourceLineNo">163</span><a name="line.163"></a>
-<span class="sourceLineNo">164</span> public long getRequestCount() {<a name="line.164"></a>
-<span class="sourceLineNo">165</span> return getHitCount() + getMissCount();<a name="line.165"></a>
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-<span class="sourceLineNo">167</span><a name="line.167"></a>
-<span class="sourceLineNo">168</span> public long getRequestCachingCount() {<a name="line.168"></a>
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-<span class="sourceLineNo">179</span><a name="line.179"></a>
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-<span class="sourceLineNo">183</span><a name="line.183"></a>
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-<span class="sourceLineNo">185</span> return hitCount.get();<a name="line.185"></a>
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-<span class="sourceLineNo">187</span><a name="line.187"></a>
-<span class="sourceLineNo">188</span> public long getPrimaryHitCount() {<a name="line.188"></a>
-<span class="sourceLineNo">189</span> return primaryHitCount.get();<a name="line.189"></a>
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-<span class="sourceLineNo">191</span><a name="line.191"></a>
-<span class="sourceLineNo">192</span> public long getHitCachingCount() {<a name="line.192"></a>
-<span class="sourceLineNo">193</span> return hitCachingCount.get();<a name="line.193"></a>
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-<span class="sourceLineNo">195</span><a name="line.195"></a>
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-<span class="sourceLineNo">199</span><a name="line.199"></a>
-<span class="sourceLineNo">200</span> public long getEvictedCount() {<a name="line.200"></a>
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-<span class="sourceLineNo">203</span><a name="line.203"></a>
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-<span class="sourceLineNo">205</span> return primaryEvictedBlockCount.get();<a name="line.205"></a>
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-<span class="sourceLineNo">207</span><a name="line.207"></a>
-<span class="sourceLineNo">208</span> public double getHitRatio() {<a name="line.208"></a>
-<span class="sourceLineNo">209</span> return ((float)getHitCount()/(float)getRequestCount());<a name="line.209"></a>
-<span class="sourceLineNo">210</span> }<a name="line.210"></a>
-<span class="sourceLineNo">211</span><a name="line.211"></a>
-<span class="sourceLineNo">212</span> public double getHitCachingRatio() {<a name="line.212"></a>
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-<span class="sourceLineNo">215</span><a name="line.215"></a>
-<span class="sourceLineNo">216</span> public double getMissRatio() {<a name="line.216"></a>
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-<span class="sourceLineNo">218</span> }<a name="line.218"></a>
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-<span class="sourceLineNo">220</span> public double getMissCachingRatio() {<a name="line.220"></a>
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-<span class="sourceLineNo">232</span> public void rollMetricsPeriod() {<a name="line.232"></a>
-<span class="sourceLineNo">233</span> hitCounts[windowIndex] = getHitCount() - lastHitCount;<a name="line.233"></a>
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-<span class="sourceLineNo">235</span> hitCachingCounts[windowIndex] =<a name="line.235"></a>
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-<span class="sourceLineNo">237</span> lastHitCachingCount = getHitCachingCount();<a name="line.237"></a>
-<span class="sourceLineNo">238</span> requestCounts[windowIndex] = getRequestCount() - lastRequestCount;<a name="line.238"></a>
-<span class="sourceLineNo">239</span> lastRequestCount = getRequestCount();<a name="line.239"></a>
-<span class="sourceLineNo">240</span> requestCachingCounts[windowIndex] =<a name="line.240"></a>
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-<span class="sourceLineNo">242</span> lastRequestCachingCount = getRequestCachingCount();<a name="line.242"></a>
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-<span class="sourceLineNo">253</span><a name="line.253"></a>
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-<span class="sourceLineNo">257</span><a name="line.257"></a>
-<span class="sourceLineNo">258</span> public long getSumRequestCachingCountsPastNPeriods() {<a name="line.258"></a>
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-<span class="sourceLineNo">262</span> public double getHitRatioPastNPeriods() {<a name="line.262"></a>
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+<span class="sourceLineNo">047</span><a name="line.47"></a>
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+<span class="sourceLineNo">050</span> <a name="line.50"></a>
+<span class="sourceLineNo">051</span> /**<a name="line.51"></a>
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+<span class="sourceLineNo">087</span> private final long [] hitCachingCounts;<a name="line.87"></a>
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+<span class="sourceLineNo">089</span> private final long [] requestCounts;<a name="line.89"></a>
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+<span class="sourceLineNo">114</span> this.hitCounts = initializeZeros(numPeriodsInWindow);<a name="line.114"></a>
+<span class="sourceLineNo">115</span> this.hitCachingCounts = initializeZeros(numPeriodsInWindow);<a name="line.115"></a>
+<span class="sourceLineNo">116</span> this.requestCounts = initializeZeros(numPeriodsInWindow);<a name="line.116"></a>
+<span class="sourceLineNo">117</span> this.requestCachingCounts = initializeZeros(numPeriodsInWindow);<a name="line.117"></a>
+<span class="sourceLineNo">118</span> this.ageAtEviction = METRICS.histogram(name(CacheStats.class, name + ".ageAtEviction"));<a name="line.118"></a>
+<span class="sourceLineNo">119</span> }<a name="line.119"></a>
+<span class="sourceLineNo">120</span><a name="line.120"></a>
+<span class="sourceLineNo">121</span> @Override<a name="line.121"></a>
+<span class="sourceLineNo">122</span> public String toString() {<a name="line.122"></a>
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+<span class="sourceLineNo">125</span> ", missCount=" + getMissCount() + ", missCachingCount=" + getMissCachingCount() +<a name="line.125"></a>
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