http://git-wip-us.apache.org/repos/asf/hbase-site/blob/bb398572/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/MemcachedBlockCache.html
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a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/MemcachedBlockCache.html
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a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/MemcachedBlockCache.html
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b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/MemcachedBlockCache.html
@@ -6,294 +6,293 @@
</head>
<body>
<div class="sourceContainer">
-<pre><span class="sourceLineNo">001</span><a name="line.1"></a>
-<span class="sourceLineNo">002</span>/**<a name="line.2"></a>
-<span class="sourceLineNo">003</span> * Copyright The Apache Software
Foundation<a name="line.3"></a>
-<span class="sourceLineNo">004</span> *<a name="line.4"></a>
-<span class="sourceLineNo">005</span> * Licensed to the Apache Software
Foundation (ASF) under one or more<a name="line.5"></a>
-<span class="sourceLineNo">006</span> * contributor license agreements. See
the NOTICE file distributed with this<a name="line.6"></a>
-<span class="sourceLineNo">007</span> * work for additional information
regarding copyright ownership. The ASF<a name="line.7"></a>
-<span class="sourceLineNo">008</span> * licenses this file to you under the
Apache License, Version 2.0 (the<a name="line.8"></a>
-<span class="sourceLineNo">009</span> * "License"); you may not use this file
except in compliance with the License.<a name="line.9"></a>
-<span class="sourceLineNo">010</span> * You may obtain a copy of the License
at<a name="line.10"></a>
-<span class="sourceLineNo">011</span> *<a name="line.11"></a>
-<span class="sourceLineNo">012</span> *
http://www.apache.org/licenses/LICENSE-2.0<a name="line.12"></a>
-<span class="sourceLineNo">013</span> *<a name="line.13"></a>
-<span class="sourceLineNo">014</span> * Unless required by applicable law or
agreed to in writing, software<a name="line.14"></a>
-<span class="sourceLineNo">015</span> * distributed under the License is
distributed on an "AS IS" BASIS, WITHOUT<a name="line.15"></a>
-<span class="sourceLineNo">016</span> * WARRANTIES OR CONDITIONS OF ANY KIND,
either express or implied. See the<a name="line.16"></a>
-<span class="sourceLineNo">017</span> * License for the specific language
governing permissions and limitations<a name="line.17"></a>
-<span class="sourceLineNo">018</span> * under the License.<a
name="line.18"></a>
-<span class="sourceLineNo">019</span> */<a name="line.19"></a>
-<span class="sourceLineNo">020</span><a name="line.20"></a>
-<span class="sourceLineNo">021</span>package
org.apache.hadoop.hbase.io.hfile;<a name="line.21"></a>
-<span class="sourceLineNo">022</span><a name="line.22"></a>
-<span class="sourceLineNo">023</span>import java.io.IOException;<a
name="line.23"></a>
-<span class="sourceLineNo">024</span>import java.net.InetSocketAddress;<a
name="line.24"></a>
-<span class="sourceLineNo">025</span>import java.nio.ByteBuffer;<a
name="line.25"></a>
-<span class="sourceLineNo">026</span>import java.util.ArrayList;<a
name="line.26"></a>
-<span class="sourceLineNo">027</span>import java.util.Iterator;<a
name="line.27"></a>
-<span class="sourceLineNo">028</span>import java.util.List;<a
name="line.28"></a>
-<span class="sourceLineNo">029</span>import
java.util.NoSuchElementException;<a name="line.29"></a>
-<span class="sourceLineNo">030</span>import
java.util.concurrent.ExecutionException;<a name="line.30"></a>
-<span class="sourceLineNo">031</span><a name="line.31"></a>
-<span class="sourceLineNo">032</span>import
org.apache.hadoop.conf.Configuration;<a name="line.32"></a>
-<span class="sourceLineNo">033</span>import
org.apache.hadoop.hbase.HConstants;<a name="line.33"></a>
-<span class="sourceLineNo">034</span>import
org.apache.hadoop.hbase.io.hfile.Cacheable.MemoryType;<a name="line.34"></a>
-<span class="sourceLineNo">035</span>import
org.apache.hadoop.hbase.nio.ByteBuff;<a name="line.35"></a>
-<span class="sourceLineNo">036</span>import
org.apache.hadoop.hbase.nio.SingleByteBuff;<a name="line.36"></a>
-<span class="sourceLineNo">037</span>import
org.apache.hadoop.hbase.trace.TraceUtil;<a name="line.37"></a>
-<span class="sourceLineNo">038</span>import
org.apache.hadoop.hbase.util.Addressing;<a name="line.38"></a>
-<span class="sourceLineNo">039</span>import
org.apache.htrace.core.TraceScope;<a name="line.39"></a>
-<span class="sourceLineNo">040</span>import
org.apache.yetus.audience.InterfaceAudience;<a name="line.40"></a>
-<span class="sourceLineNo">041</span>import org.slf4j.Logger;<a
name="line.41"></a>
-<span class="sourceLineNo">042</span>import org.slf4j.LoggerFactory;<a
name="line.42"></a>
-<span class="sourceLineNo">043</span><a name="line.43"></a>
-<span class="sourceLineNo">044</span>import net.spy.memcached.CachedData;<a
name="line.44"></a>
-<span class="sourceLineNo">045</span>import
net.spy.memcached.ConnectionFactoryBuilder;<a name="line.45"></a>
-<span class="sourceLineNo">046</span>import net.spy.memcached.FailureMode;<a
name="line.46"></a>
-<span class="sourceLineNo">047</span>import
net.spy.memcached.MemcachedClient;<a name="line.47"></a>
-<span class="sourceLineNo">048</span>import
net.spy.memcached.transcoders.Transcoder;<a name="line.48"></a>
-<span class="sourceLineNo">049</span><a name="line.49"></a>
-<span class="sourceLineNo">050</span>/**<a name="line.50"></a>
-<span class="sourceLineNo">051</span> * Class to store blocks into
memcached.<a name="line.51"></a>
-<span class="sourceLineNo">052</span> * This should only be used on a cluster
of Memcached daemons that are tuned well and have a<a name="line.52"></a>
-<span class="sourceLineNo">053</span> * good network connection to the HBase
regionservers. Any other use will likely slow down HBase<a name="line.53"></a>
-<span class="sourceLineNo">054</span> * greatly.<a name="line.54"></a>
-<span class="sourceLineNo">055</span> */<a name="line.55"></a>
-<span class="sourceLineNo">056</span>@InterfaceAudience.Private<a
name="line.56"></a>
-<span class="sourceLineNo">057</span>public class MemcachedBlockCache
implements BlockCache {<a name="line.57"></a>
-<span class="sourceLineNo">058</span> private static final Logger LOG =
LoggerFactory.getLogger(MemcachedBlockCache.class.getName());<a
name="line.58"></a>
-<span class="sourceLineNo">059</span><a name="line.59"></a>
-<span class="sourceLineNo">060</span> // Some memcache versions won't take
more than 1024 * 1024. So set the limit below<a name="line.60"></a>
-<span class="sourceLineNo">061</span> // that just in case this client is
used with those versions.<a name="line.61"></a>
-<span class="sourceLineNo">062</span> public static final int MAX_SIZE = 1020
* 1024;<a name="line.62"></a>
-<span class="sourceLineNo">063</span><a name="line.63"></a>
-<span class="sourceLineNo">064</span> // Config key for what memcached
servers to use.<a name="line.64"></a>
-<span class="sourceLineNo">065</span> // They should be specified in a comma
sperated list with ports.<a name="line.65"></a>
-<span class="sourceLineNo">066</span> // like:<a name="line.66"></a>
-<span class="sourceLineNo">067</span> //<a name="line.67"></a>
-<span class="sourceLineNo">068</span> // host1:11211,host3:8080,host4:11211<a
name="line.68"></a>
-<span class="sourceLineNo">069</span> public static final String
MEMCACHED_CONFIG_KEY = "hbase.cache.memcached.servers";<a name="line.69"></a>
-<span class="sourceLineNo">070</span> public static final String
MEMCACHED_TIMEOUT_KEY = "hbase.cache.memcached.timeout";<a name="line.70"></a>
-<span class="sourceLineNo">071</span> public static final String
MEMCACHED_OPTIMEOUT_KEY = "hbase.cache.memcached.optimeout";<a
name="line.71"></a>
-<span class="sourceLineNo">072</span> public static final String
MEMCACHED_OPTIMIZE_KEY = "hbase.cache.memcached.spy.optimze";<a
name="line.72"></a>
-<span class="sourceLineNo">073</span> public static final long
MEMCACHED_DEFAULT_TIMEOUT = 500;<a name="line.73"></a>
-<span class="sourceLineNo">074</span> public static final boolean
MEMCACHED_OPTIMIZE_DEFAULT = false;<a name="line.74"></a>
-<span class="sourceLineNo">075</span><a name="line.75"></a>
-<span class="sourceLineNo">076</span> private final MemcachedClient client;<a
name="line.76"></a>
-<span class="sourceLineNo">077</span> private final HFileBlockTranscoder tc =
new HFileBlockTranscoder();<a name="line.77"></a>
-<span class="sourceLineNo">078</span> private final CacheStats cacheStats =
new CacheStats("MemcachedBlockCache");<a name="line.78"></a>
-<span class="sourceLineNo">079</span><a name="line.79"></a>
-<span class="sourceLineNo">080</span> public
MemcachedBlockCache(Configuration c) throws IOException {<a name="line.80"></a>
-<span class="sourceLineNo">081</span> LOG.info("Creating
MemcachedBlockCache");<a name="line.81"></a>
-<span class="sourceLineNo">082</span><a name="line.82"></a>
-<span class="sourceLineNo">083</span> long opTimeout =
c.getLong(MEMCACHED_OPTIMEOUT_KEY, MEMCACHED_DEFAULT_TIMEOUT);<a
name="line.83"></a>
-<span class="sourceLineNo">084</span> long queueTimeout =
c.getLong(MEMCACHED_TIMEOUT_KEY, opTimeout + MEMCACHED_DEFAULT_TIMEOUT);<a
name="line.84"></a>
-<span class="sourceLineNo">085</span> boolean optimize =
c.getBoolean(MEMCACHED_OPTIMIZE_KEY, MEMCACHED_OPTIMIZE_DEFAULT);<a
name="line.85"></a>
-<span class="sourceLineNo">086</span><a name="line.86"></a>
-<span class="sourceLineNo">087</span> ConnectionFactoryBuilder builder =
new ConnectionFactoryBuilder()<a name="line.87"></a>
-<span class="sourceLineNo">088</span> .setOpTimeout(opTimeout)<a
name="line.88"></a>
-<span class="sourceLineNo">089</span>
.setOpQueueMaxBlockTime(queueTimeout) // Cap the max time before anything times
out<a name="line.89"></a>
-<span class="sourceLineNo">090</span>
.setFailureMode(FailureMode.Redistribute)<a name="line.90"></a>
-<span class="sourceLineNo">091</span> .setShouldOptimize(optimize)<a
name="line.91"></a>
-<span class="sourceLineNo">092</span> .setDaemon(true)
// Don't keep threads around past the end of days.<a name="line.92"></a>
-<span class="sourceLineNo">093</span> .setUseNagleAlgorithm(false)
// Ain't nobody got time for that<a name="line.93"></a>
-<span class="sourceLineNo">094</span>
.setReadBufferSize(HConstants.DEFAULT_BLOCKSIZE * 4 * 1024); // Much larger
just in case<a name="line.94"></a>
-<span class="sourceLineNo">095</span><a name="line.95"></a>
-<span class="sourceLineNo">096</span> // Assume only the localhost is
serving memecached.<a name="line.96"></a>
-<span class="sourceLineNo">097</span> // A la mcrouter or co-locating
memcached with split regionservers.<a name="line.97"></a>
-<span class="sourceLineNo">098</span> //<a name="line.98"></a>
-<span class="sourceLineNo">099</span> // If this config is a pool of
memecached servers they will all be used according to the<a name="line.99"></a>
-<span class="sourceLineNo">100</span> // default hashing scheme defined by
the memcache client. Spy Memecache client in this<a name="line.100"></a>
-<span class="sourceLineNo">101</span> // case.<a name="line.101"></a>
-<span class="sourceLineNo">102</span> String serverListString =
c.get(MEMCACHED_CONFIG_KEY,"localhost:11211");<a name="line.102"></a>
-<span class="sourceLineNo">103</span> String[] servers =
serverListString.split(",");<a name="line.103"></a>
-<span class="sourceLineNo">104</span> List<InetSocketAddress>
serverAddresses = new ArrayList<>(servers.length);<a name="line.104"></a>
-<span class="sourceLineNo">105</span> for (String s:servers) {<a
name="line.105"></a>
-<span class="sourceLineNo">106</span>
serverAddresses.add(Addressing.createInetSocketAddressFromHostAndPortStr(s));<a
name="line.106"></a>
-<span class="sourceLineNo">107</span> }<a name="line.107"></a>
-<span class="sourceLineNo">108</span><a name="line.108"></a>
-<span class="sourceLineNo">109</span> client = new
MemcachedClient(builder.build(), serverAddresses);<a name="line.109"></a>
-<span class="sourceLineNo">110</span> }<a name="line.110"></a>
-<span class="sourceLineNo">111</span><a name="line.111"></a>
-<span class="sourceLineNo">112</span> @Override<a name="line.112"></a>
-<span class="sourceLineNo">113</span> public void cacheBlock(BlockCacheKey
cacheKey, Cacheable buf, boolean inMemory) {<a name="line.113"></a>
-<span class="sourceLineNo">114</span> cacheBlock(cacheKey, buf);<a
name="line.114"></a>
-<span class="sourceLineNo">115</span> }<a name="line.115"></a>
-<span class="sourceLineNo">116</span><a name="line.116"></a>
-<span class="sourceLineNo">117</span> @Override<a name="line.117"></a>
-<span class="sourceLineNo">118</span> public void cacheBlock(BlockCacheKey
cacheKey, Cacheable buf) {<a name="line.118"></a>
-<span class="sourceLineNo">119</span> if (buf instanceof HFileBlock) {<a
name="line.119"></a>
-<span class="sourceLineNo">120</span> client.add(cacheKey.toString(),
MAX_SIZE, (HFileBlock) buf, tc);<a name="line.120"></a>
-<span class="sourceLineNo">121</span> } else {<a name="line.121"></a>
-<span class="sourceLineNo">122</span> if (LOG.isDebugEnabled()) {<a
name="line.122"></a>
-<span class="sourceLineNo">123</span> LOG.debug("MemcachedBlockCache
can not cache Cacheable's of type "<a name="line.123"></a>
-<span class="sourceLineNo">124</span> +
buf.getClass().toString());<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><a name="line.128"></a>
-<span class="sourceLineNo">129</span> @Override<a name="line.129"></a>
-<span class="sourceLineNo">130</span> public Cacheable getBlock(BlockCacheKey
cacheKey, boolean caching,<a name="line.130"></a>
-<span class="sourceLineNo">131</span> boolean
repeat, boolean updateCacheMetrics) {<a name="line.131"></a>
-<span class="sourceLineNo">132</span> // Assume that nothing is the block
cache<a name="line.132"></a>
-<span class="sourceLineNo">133</span> HFileBlock result = null;<a
name="line.133"></a>
-<span class="sourceLineNo">134</span><a name="line.134"></a>
-<span class="sourceLineNo">135</span> try (TraceScope traceScope =
TraceUtil.createTrace("MemcachedBlockCache.getBlock")) {<a name="line.135"></a>
-<span class="sourceLineNo">136</span> result =
client.get(cacheKey.toString(), tc);<a name="line.136"></a>
-<span class="sourceLineNo">137</span> } catch (Exception e) {<a
name="line.137"></a>
-<span class="sourceLineNo">138</span> // Catch a pretty broad set of
exceptions to limit any changes in the memecache client<a name="line.138"></a>
-<span class="sourceLineNo">139</span> // and how it handles failures from
leaking into the read path.<a name="line.139"></a>
-<span class="sourceLineNo">140</span> if (LOG.isDebugEnabled()) {<a
name="line.140"></a>
-<span class="sourceLineNo">141</span> LOG.debug("Exception pulling from
memcached [ "<a name="line.141"></a>
-<span class="sourceLineNo">142</span> + cacheKey.toString()<a
name="line.142"></a>
-<span class="sourceLineNo">143</span> + " ]. Treating as a miss.",
e);<a name="line.143"></a>
-<span class="sourceLineNo">144</span> }<a name="line.144"></a>
-<span class="sourceLineNo">145</span> result = null;<a
name="line.145"></a>
-<span class="sourceLineNo">146</span> } finally {<a name="line.146"></a>
-<span class="sourceLineNo">147</span> // Update stats if this request
doesn't have it turned off 100% of the time<a name="line.147"></a>
-<span class="sourceLineNo">148</span> if (updateCacheMetrics) {<a
name="line.148"></a>
-<span class="sourceLineNo">149</span> if (result == null) {<a
name="line.149"></a>
-<span class="sourceLineNo">150</span> cacheStats.miss(caching,
cacheKey.isPrimary(), cacheKey.getBlockType());<a name="line.150"></a>
-<span class="sourceLineNo">151</span> } else {<a name="line.151"></a>
-<span class="sourceLineNo">152</span> cacheStats.hit(caching,
cacheKey.isPrimary(), cacheKey.getBlockType());<a name="line.152"></a>
-<span class="sourceLineNo">153</span> }<a name="line.153"></a>
-<span class="sourceLineNo">154</span> }<a name="line.154"></a>
-<span class="sourceLineNo">155</span> }<a name="line.155"></a>
-<span class="sourceLineNo">156</span><a name="line.156"></a>
-<span class="sourceLineNo">157</span> return result;<a name="line.157"></a>
-<span class="sourceLineNo">158</span> }<a name="line.158"></a>
-<span class="sourceLineNo">159</span><a name="line.159"></a>
-<span class="sourceLineNo">160</span> @Override<a name="line.160"></a>
-<span class="sourceLineNo">161</span> public boolean evictBlock(BlockCacheKey
cacheKey) {<a name="line.161"></a>
-<span class="sourceLineNo">162</span> try {<a name="line.162"></a>
-<span class="sourceLineNo">163</span> cacheStats.evict();<a
name="line.163"></a>
-<span class="sourceLineNo">164</span> return
client.delete(cacheKey.toString()).get();<a name="line.164"></a>
-<span class="sourceLineNo">165</span> } catch (InterruptedException e) {<a
name="line.165"></a>
-<span class="sourceLineNo">166</span> LOG.warn("Error deleting " +
cacheKey.toString(), e);<a name="line.166"></a>
-<span class="sourceLineNo">167</span>
Thread.currentThread().interrupt();<a name="line.167"></a>
-<span class="sourceLineNo">168</span> } catch (ExecutionException e) {<a
name="line.168"></a>
-<span class="sourceLineNo">169</span> if (LOG.isDebugEnabled()) {<a
name="line.169"></a>
-<span class="sourceLineNo">170</span> LOG.debug("Error deleting " +
cacheKey.toString(), e);<a name="line.170"></a>
-<span class="sourceLineNo">171</span> }<a name="line.171"></a>
-<span class="sourceLineNo">172</span> }<a name="line.172"></a>
-<span class="sourceLineNo">173</span> return false;<a name="line.173"></a>
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-<span class="sourceLineNo">175</span><a name="line.175"></a>
-<span class="sourceLineNo">176</span> /**<a name="line.176"></a>
-<span class="sourceLineNo">177</span> * This method does nothing so that
memcached can handle all evictions.<a name="line.177"></a>
-<span class="sourceLineNo">178</span> */<a name="line.178"></a>
-<span class="sourceLineNo">179</span> @Override<a name="line.179"></a>
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evictBlocksByHfileName(String hfileName) {<a name="line.180"></a>
-<span class="sourceLineNo">181</span> return 0;<a name="line.181"></a>
-<span class="sourceLineNo">182</span> }<a name="line.182"></a>
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-<span class="sourceLineNo">184</span> @Override<a name="line.184"></a>
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name="line.185"></a>
-<span class="sourceLineNo">186</span> return cacheStats;<a
name="line.186"></a>
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-<span class="sourceLineNo">189</span> @Override<a name="line.189"></a>
-<span class="sourceLineNo">190</span> public void shutdown() {<a
name="line.190"></a>
-<span class="sourceLineNo">191</span> client.shutdown();<a
name="line.191"></a>
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name="line.195"></a>
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name="line.220"></a>
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Iterator<CachedBlock>() {<a name="line.231"></a>
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name="line.233"></a>
-<span class="sourceLineNo">234</span> return false;<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> @Override<a name="line.237"></a>
-<span class="sourceLineNo">238</span> public CachedBlock next() {<a
name="line.238"></a>
-<span class="sourceLineNo">239</span> throw new
NoSuchElementException("MemcachedBlockCache can't iterate over blocks.");<a
name="line.239"></a>
-<span class="sourceLineNo">240</span> }<a name="line.240"></a>
-<span class="sourceLineNo">241</span><a name="line.241"></a>
-<span class="sourceLineNo">242</span> @Override<a name="line.242"></a>
-<span class="sourceLineNo">243</span> public void remove() {<a
name="line.243"></a>
-<span class="sourceLineNo">244</span><a name="line.244"></a>
-<span class="sourceLineNo">245</span> }<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> @Override<a name="line.249"></a>
-<span class="sourceLineNo">250</span> public BlockCache[] getBlockCaches()
{<a name="line.250"></a>
-<span class="sourceLineNo">251</span> return null;<a name="line.251"></a>
-<span class="sourceLineNo">252</span> }<a name="line.252"></a>
-<span class="sourceLineNo">253</span><a name="line.253"></a>
-<span class="sourceLineNo">254</span> /**<a name="line.254"></a>
-<span class="sourceLineNo">255</span> * Class to encode and decode an
HFileBlock to and from memecached's resulting byte arrays.<a
name="line.255"></a>
-<span class="sourceLineNo">256</span> */<a name="line.256"></a>
-<span class="sourceLineNo">257</span> private static class
HFileBlockTranscoder implements Transcoder<HFileBlock> {<a
name="line.257"></a>
-<span class="sourceLineNo">258</span><a name="line.258"></a>
-<span class="sourceLineNo">259</span> @Override<a name="line.259"></a>
-<span class="sourceLineNo">260</span> public boolean asyncDecode(CachedData
d) {<a name="line.260"></a>
-<span class="sourceLineNo">261</span> return false;<a name="line.261"></a>
-<span class="sourceLineNo">262</span> }<a name="line.262"></a>
-<span class="sourceLineNo">263</span><a name="line.263"></a>
-<span class="sourceLineNo">264</span> @Override<a name="line.264"></a>
-<span class="sourceLineNo">265</span> public CachedData encode(HFileBlock
block) {<a name="line.265"></a>
-<span class="sourceLineNo">266</span> ByteBuffer bb =
ByteBuffer.allocate(block.getSerializedLength());<a name="line.266"></a>
-<span class="sourceLineNo">267</span> block.serialize(bb);<a
name="line.267"></a>
-<span class="sourceLineNo">268</span> return new CachedData(0,
bb.array(), CachedData.MAX_SIZE);<a name="line.268"></a>
-<span class="sourceLineNo">269</span> }<a name="line.269"></a>
-<span class="sourceLineNo">270</span><a name="line.270"></a>
-<span class="sourceLineNo">271</span> @Override<a name="line.271"></a>
-<span class="sourceLineNo">272</span> public HFileBlock decode(CachedData
d) {<a name="line.272"></a>
-<span class="sourceLineNo">273</span> try {<a name="line.273"></a>
-<span class="sourceLineNo">274</span> ByteBuff buf = new
SingleByteBuff(ByteBuffer.wrap(d.getData()));<a name="line.274"></a>
-<span class="sourceLineNo">275</span> return (HFileBlock)
HFileBlock.BLOCK_DESERIALIZER.deserialize(buf, true,<a name="line.275"></a>
-<span class="sourceLineNo">276</span> MemoryType.EXCLUSIVE);<a
name="line.276"></a>
-<span class="sourceLineNo">277</span> } catch (IOException e) {<a
name="line.277"></a>
-<span class="sourceLineNo">278</span> LOG.warn("Error deserializing
data from memcached",e);<a name="line.278"></a>
-<span class="sourceLineNo">279</span> }<a name="line.279"></a>
-<span class="sourceLineNo">280</span> return null;<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> @Override<a name="line.283"></a>
-<span class="sourceLineNo">284</span> public int getMaxSize() {<a
name="line.284"></a>
-<span class="sourceLineNo">285</span> return MAX_SIZE;<a
name="line.285"></a>
-<span class="sourceLineNo">286</span> }<a name="line.286"></a>
-<span class="sourceLineNo">287</span> }<a name="line.287"></a>
-<span class="sourceLineNo">288</span>}<a name="line.288"></a>
+<pre><span class="sourceLineNo">001</span>/**<a name="line.1"></a>
+<span class="sourceLineNo">002</span> * Copyright The Apache Software
Foundation<a name="line.2"></a>
+<span class="sourceLineNo">003</span> *<a name="line.3"></a>
+<span class="sourceLineNo">004</span> * Licensed to the Apache Software
Foundation (ASF) under one or more<a name="line.4"></a>
+<span class="sourceLineNo">005</span> * contributor license agreements. See
the NOTICE file distributed with this<a name="line.5"></a>
+<span class="sourceLineNo">006</span> * work for additional information
regarding copyright ownership. The ASF<a name="line.6"></a>
+<span class="sourceLineNo">007</span> * licenses this file 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 with the License.<a name="line.8"></a>
+<span class="sourceLineNo">009</span> * 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, WITHOUT<a name="line.14"></a>
+<span class="sourceLineNo">015</span> * WARRANTIES OR CONDITIONS OF ANY KIND,
either express or implied. See the<a name="line.15"></a>
+<span class="sourceLineNo">016</span> * License for the specific language
governing permissions and limitations<a name="line.16"></a>
+<span class="sourceLineNo">017</span> * 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.io.hfile;<a name="line.20"></a>
+<span class="sourceLineNo">021</span><a name="line.21"></a>
+<span class="sourceLineNo">022</span>import java.io.IOException;<a
name="line.22"></a>
+<span class="sourceLineNo">023</span>import java.net.InetSocketAddress;<a
name="line.23"></a>
+<span class="sourceLineNo">024</span>import java.nio.ByteBuffer;<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.Iterator;<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.NoSuchElementException;<a name="line.28"></a>
+<span class="sourceLineNo">029</span>import
java.util.concurrent.ExecutionException;<a name="line.29"></a>
+<span class="sourceLineNo">030</span><a name="line.30"></a>
+<span class="sourceLineNo">031</span>import net.spy.memcached.CachedData;<a
name="line.31"></a>
+<span class="sourceLineNo">032</span>import
net.spy.memcached.ConnectionFactoryBuilder;<a name="line.32"></a>
+<span class="sourceLineNo">033</span>import net.spy.memcached.FailureMode;<a
name="line.33"></a>
+<span class="sourceLineNo">034</span>import
net.spy.memcached.MemcachedClient;<a name="line.34"></a>
+<span class="sourceLineNo">035</span>import
net.spy.memcached.transcoders.Transcoder;<a name="line.35"></a>
+<span class="sourceLineNo">036</span><a name="line.36"></a>
+<span class="sourceLineNo">037</span>import
org.apache.hadoop.conf.Configuration;<a name="line.37"></a>
+<span class="sourceLineNo">038</span>import
org.apache.hadoop.hbase.HConstants;<a name="line.38"></a>
+<span class="sourceLineNo">039</span>import
org.apache.hadoop.hbase.io.hfile.Cacheable.MemoryType;<a name="line.39"></a>
+<span class="sourceLineNo">040</span>import
org.apache.hadoop.hbase.nio.ByteBuff;<a name="line.40"></a>
+<span class="sourceLineNo">041</span>import
org.apache.hadoop.hbase.nio.SingleByteBuff;<a name="line.41"></a>
+<span class="sourceLineNo">042</span>import
org.apache.hadoop.hbase.trace.TraceUtil;<a name="line.42"></a>
+<span class="sourceLineNo">043</span>import
org.apache.hadoop.hbase.util.Addressing;<a name="line.43"></a>
+<span class="sourceLineNo">044</span>import
org.apache.htrace.core.TraceScope;<a name="line.44"></a>
+<span class="sourceLineNo">045</span>import
org.apache.yetus.audience.InterfaceAudience;<a name="line.45"></a>
+<span class="sourceLineNo">046</span>import org.slf4j.Logger;<a
name="line.46"></a>
+<span class="sourceLineNo">047</span>import org.slf4j.LoggerFactory;<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> * Class to store blocks into
memcached.<a name="line.50"></a>
+<span class="sourceLineNo">051</span> * This should only be used on a cluster
of Memcached daemons that are tuned well and have a<a name="line.51"></a>
+<span class="sourceLineNo">052</span> * good network connection to the HBase
regionservers. Any other use will likely slow down HBase<a name="line.52"></a>
+<span class="sourceLineNo">053</span> * greatly.<a name="line.53"></a>
+<span class="sourceLineNo">054</span> */<a name="line.54"></a>
+<span class="sourceLineNo">055</span>@InterfaceAudience.Private<a
name="line.55"></a>
+<span class="sourceLineNo">056</span>public class MemcachedBlockCache
implements BlockCache {<a name="line.56"></a>
+<span class="sourceLineNo">057</span> private static final Logger LOG =
LoggerFactory.getLogger(MemcachedBlockCache.class.getName());<a
name="line.57"></a>
+<span class="sourceLineNo">058</span><a name="line.58"></a>
+<span class="sourceLineNo">059</span> // Some memcache versions won't take
more than 1024 * 1024. So set the limit below<a name="line.59"></a>
+<span class="sourceLineNo">060</span> // that just in case this client is
used with those versions.<a name="line.60"></a>
+<span class="sourceLineNo">061</span> public static final int MAX_SIZE = 1020
* 1024;<a name="line.61"></a>
+<span class="sourceLineNo">062</span><a name="line.62"></a>
+<span class="sourceLineNo">063</span> // Config key for what memcached
servers to use.<a name="line.63"></a>
+<span class="sourceLineNo">064</span> // They should be specified in a comma
sperated list with ports.<a name="line.64"></a>
+<span class="sourceLineNo">065</span> // like:<a name="line.65"></a>
+<span class="sourceLineNo">066</span> //<a name="line.66"></a>
+<span class="sourceLineNo">067</span> // host1:11211,host3:8080,host4:11211<a
name="line.67"></a>
+<span class="sourceLineNo">068</span> public static final String
MEMCACHED_CONFIG_KEY = "hbase.cache.memcached.servers";<a name="line.68"></a>
+<span class="sourceLineNo">069</span> public static final String
MEMCACHED_TIMEOUT_KEY = "hbase.cache.memcached.timeout";<a name="line.69"></a>
+<span class="sourceLineNo">070</span> public static final String
MEMCACHED_OPTIMEOUT_KEY = "hbase.cache.memcached.optimeout";<a
name="line.70"></a>
+<span class="sourceLineNo">071</span> public static final String
MEMCACHED_OPTIMIZE_KEY = "hbase.cache.memcached.spy.optimze";<a
name="line.71"></a>
+<span class="sourceLineNo">072</span> public static final long
MEMCACHED_DEFAULT_TIMEOUT = 500;<a name="line.72"></a>
+<span class="sourceLineNo">073</span> public static final boolean
MEMCACHED_OPTIMIZE_DEFAULT = false;<a name="line.73"></a>
+<span class="sourceLineNo">074</span><a name="line.74"></a>
+<span class="sourceLineNo">075</span> private final MemcachedClient client;<a
name="line.75"></a>
+<span class="sourceLineNo">076</span> private final HFileBlockTranscoder tc =
new HFileBlockTranscoder();<a name="line.76"></a>
+<span class="sourceLineNo">077</span> private final CacheStats cacheStats =
new CacheStats("MemcachedBlockCache");<a name="line.77"></a>
+<span class="sourceLineNo">078</span><a name="line.78"></a>
+<span class="sourceLineNo">079</span> public
MemcachedBlockCache(Configuration c) throws IOException {<a name="line.79"></a>
+<span class="sourceLineNo">080</span> LOG.info("Creating
MemcachedBlockCache");<a name="line.80"></a>
+<span class="sourceLineNo">081</span><a name="line.81"></a>
+<span class="sourceLineNo">082</span> long opTimeout =
c.getLong(MEMCACHED_OPTIMEOUT_KEY, MEMCACHED_DEFAULT_TIMEOUT);<a
name="line.82"></a>
+<span class="sourceLineNo">083</span> long queueTimeout =
c.getLong(MEMCACHED_TIMEOUT_KEY, opTimeout + MEMCACHED_DEFAULT_TIMEOUT);<a
name="line.83"></a>
+<span class="sourceLineNo">084</span> boolean optimize =
c.getBoolean(MEMCACHED_OPTIMIZE_KEY, MEMCACHED_OPTIMIZE_DEFAULT);<a
name="line.84"></a>
+<span class="sourceLineNo">085</span><a name="line.85"></a>
+<span class="sourceLineNo">086</span> ConnectionFactoryBuilder builder =
new ConnectionFactoryBuilder()<a name="line.86"></a>
+<span class="sourceLineNo">087</span> .setOpTimeout(opTimeout)<a
name="line.87"></a>
+<span class="sourceLineNo">088</span>
.setOpQueueMaxBlockTime(queueTimeout) // Cap the max time before anything times
out<a name="line.88"></a>
+<span class="sourceLineNo">089</span>
.setFailureMode(FailureMode.Redistribute)<a name="line.89"></a>
+<span class="sourceLineNo">090</span> .setShouldOptimize(optimize)<a
name="line.90"></a>
+<span class="sourceLineNo">091</span> .setDaemon(true)
// Don't keep threads around past the end of days.<a name="line.91"></a>
+<span class="sourceLineNo">092</span> .setUseNagleAlgorithm(false)
// Ain't nobody got time for that<a name="line.92"></a>
+<span class="sourceLineNo">093</span>
.setReadBufferSize(HConstants.DEFAULT_BLOCKSIZE * 4 * 1024); // Much larger
just in case<a name="line.93"></a>
+<span class="sourceLineNo">094</span><a name="line.94"></a>
+<span class="sourceLineNo">095</span> // Assume only the localhost is
serving memecached.<a name="line.95"></a>
+<span class="sourceLineNo">096</span> // A la mcrouter or co-locating
memcached with split regionservers.<a name="line.96"></a>
+<span class="sourceLineNo">097</span> //<a name="line.97"></a>
+<span class="sourceLineNo">098</span> // If this config is a pool of
memecached servers they will all be used according to the<a name="line.98"></a>
+<span class="sourceLineNo">099</span> // default hashing scheme defined by
the memcache client. Spy Memecache client in this<a name="line.99"></a>
+<span class="sourceLineNo">100</span> // case.<a name="line.100"></a>
+<span class="sourceLineNo">101</span> String serverListString =
c.get(MEMCACHED_CONFIG_KEY,"localhost:11211");<a name="line.101"></a>
+<span class="sourceLineNo">102</span> String[] servers =
serverListString.split(",");<a name="line.102"></a>
+<span class="sourceLineNo">103</span> List<InetSocketAddress>
serverAddresses = new ArrayList<>(servers.length);<a name="line.103"></a>
+<span class="sourceLineNo">104</span> for (String s:servers) {<a
name="line.104"></a>
+<span class="sourceLineNo">105</span>
serverAddresses.add(Addressing.createInetSocketAddressFromHostAndPortStr(s));<a
name="line.105"></a>
+<span class="sourceLineNo">106</span> }<a name="line.106"></a>
+<span class="sourceLineNo">107</span><a name="line.107"></a>
+<span class="sourceLineNo">108</span> client = new
MemcachedClient(builder.build(), serverAddresses);<a name="line.108"></a>
+<span class="sourceLineNo">109</span> }<a name="line.109"></a>
+<span class="sourceLineNo">110</span><a name="line.110"></a>
+<span class="sourceLineNo">111</span> @Override<a name="line.111"></a>
+<span class="sourceLineNo">112</span> public void cacheBlock(BlockCacheKey
cacheKey, Cacheable buf, boolean inMemory) {<a name="line.112"></a>
+<span class="sourceLineNo">113</span> cacheBlock(cacheKey, buf);<a
name="line.113"></a>
+<span class="sourceLineNo">114</span> }<a name="line.114"></a>
+<span class="sourceLineNo">115</span><a name="line.115"></a>
+<span class="sourceLineNo">116</span> @Override<a name="line.116"></a>
+<span class="sourceLineNo">117</span> public void cacheBlock(BlockCacheKey
cacheKey, Cacheable buf) {<a name="line.117"></a>
+<span class="sourceLineNo">118</span> if (buf instanceof HFileBlock) {<a
name="line.118"></a>
+<span class="sourceLineNo">119</span> client.add(cacheKey.toString(),
MAX_SIZE, (HFileBlock) buf, tc);<a name="line.119"></a>
+<span class="sourceLineNo">120</span> } else {<a name="line.120"></a>
+<span class="sourceLineNo">121</span> if (LOG.isDebugEnabled()) {<a
name="line.121"></a>
+<span class="sourceLineNo">122</span> LOG.debug("MemcachedBlockCache
can not cache Cacheable's of type "<a name="line.122"></a>
+<span class="sourceLineNo">123</span> +
buf.getClass().toString());<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> @Override<a name="line.128"></a>
+<span class="sourceLineNo">129</span> public Cacheable getBlock(BlockCacheKey
cacheKey, boolean caching,<a name="line.129"></a>
+<span class="sourceLineNo">130</span> boolean
repeat, boolean updateCacheMetrics) {<a name="line.130"></a>
+<span class="sourceLineNo">131</span> // Assume that nothing is the block
cache<a name="line.131"></a>
+<span class="sourceLineNo">132</span> HFileBlock result = null;<a
name="line.132"></a>
+<span class="sourceLineNo">133</span><a name="line.133"></a>
+<span class="sourceLineNo">134</span> try (TraceScope traceScope =
TraceUtil.createTrace("MemcachedBlockCache.getBlock")) {<a name="line.134"></a>
+<span class="sourceLineNo">135</span> result =
client.get(cacheKey.toString(), tc);<a name="line.135"></a>
+<span class="sourceLineNo">136</span> } catch (Exception e) {<a
name="line.136"></a>
+<span class="sourceLineNo">137</span> // Catch a pretty broad set of
exceptions to limit any changes in the memecache client<a name="line.137"></a>
+<span class="sourceLineNo">138</span> // and how it handles failures from
leaking into the read path.<a name="line.138"></a>
+<span class="sourceLineNo">139</span> if (LOG.isDebugEnabled()) {<a
name="line.139"></a>
+<span class="sourceLineNo">140</span> LOG.debug("Exception pulling from
memcached [ "<a name="line.140"></a>
+<span class="sourceLineNo">141</span> + cacheKey.toString()<a
name="line.141"></a>
+<span class="sourceLineNo">142</span> + " ]. Treating as a miss.",
e);<a name="line.142"></a>
+<span class="sourceLineNo">143</span> }<a name="line.143"></a>
+<span class="sourceLineNo">144</span> result = null;<a
name="line.144"></a>
+<span class="sourceLineNo">145</span> } finally {<a name="line.145"></a>
+<span class="sourceLineNo">146</span> // Update stats if this request
doesn't have it turned off 100% of the time<a name="line.146"></a>
+<span class="sourceLineNo">147</span> if (updateCacheMetrics) {<a
name="line.147"></a>
+<span class="sourceLineNo">148</span> if (result == null) {<a
name="line.148"></a>
+<span class="sourceLineNo">149</span> cacheStats.miss(caching,
cacheKey.isPrimary(), cacheKey.getBlockType());<a name="line.149"></a>
+<span class="sourceLineNo">150</span> } else {<a name="line.150"></a>
+<span class="sourceLineNo">151</span> cacheStats.hit(caching,
cacheKey.isPrimary(), cacheKey.getBlockType());<a name="line.151"></a>
+<span class="sourceLineNo">152</span> }<a name="line.152"></a>
+<span class="sourceLineNo">153</span> }<a name="line.153"></a>
+<span class="sourceLineNo">154</span> }<a name="line.154"></a>
+<span class="sourceLineNo">155</span><a name="line.155"></a>
+<span class="sourceLineNo">156</span> return result;<a name="line.156"></a>
+<span class="sourceLineNo">157</span> }<a name="line.157"></a>
+<span class="sourceLineNo">158</span><a name="line.158"></a>
+<span class="sourceLineNo">159</span> @Override<a name="line.159"></a>
+<span class="sourceLineNo">160</span> public boolean evictBlock(BlockCacheKey
cacheKey) {<a name="line.160"></a>
+<span class="sourceLineNo">161</span> try {<a name="line.161"></a>
+<span class="sourceLineNo">162</span> cacheStats.evict();<a
name="line.162"></a>
+<span class="sourceLineNo">163</span> return
client.delete(cacheKey.toString()).get();<a name="line.163"></a>
+<span class="sourceLineNo">164</span> } catch (InterruptedException e) {<a
name="line.164"></a>
+<span class="sourceLineNo">165</span> LOG.warn("Error deleting " +
cacheKey.toString(), e);<a name="line.165"></a>
+<span class="sourceLineNo">166</span>
Thread.currentThread().interrupt();<a name="line.166"></a>
+<span class="sourceLineNo">167</span> } catch (ExecutionException e) {<a
name="line.167"></a>
+<span class="sourceLineNo">168</span> if (LOG.isDebugEnabled()) {<a
name="line.168"></a>
+<span class="sourceLineNo">169</span> LOG.debug("Error deleting " +
cacheKey.toString(), e);<a name="line.169"></a>
+<span class="sourceLineNo">170</span> }<a name="line.170"></a>
+<span class="sourceLineNo">171</span> }<a name="line.171"></a>
+<span class="sourceLineNo">172</span> return false;<a name="line.172"></a>
+<span class="sourceLineNo">173</span> }<a name="line.173"></a>
+<span class="sourceLineNo">174</span><a name="line.174"></a>
+<span class="sourceLineNo">175</span> /**<a name="line.175"></a>
+<span class="sourceLineNo">176</span> * This method does nothing so that
memcached can handle all evictions.<a name="line.176"></a>
+<span class="sourceLineNo">177</span> */<a name="line.177"></a>
+<span class="sourceLineNo">178</span> @Override<a name="line.178"></a>
+<span class="sourceLineNo">179</span> public int
evictBlocksByHfileName(String hfileName) {<a name="line.179"></a>
+<span class="sourceLineNo">180</span> return 0;<a name="line.180"></a>
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