content/doc/4.0-alpha4/operating/compaction/stcs.html - cassandra-website - Git at Google

 <!DOCTYPE html>
 <html>


 <head>
   <meta charset="utf-8">
   <meta http-equiv="X-UA-Compatible" content="IE=edge">
   <meta name="viewport" content="width=device-width, initial-scale=1">
   <meta name="description" content="The Apache Cassandra database is the right choice when you need scalability and high availability without compromising performance. Linear scalability and proven fault-tolerance on commodity hardware or cloud infrastructure make it the perfect platform for mission-critical data. Cassandra's support for replicating across multiple datacenters is best-in-class, providing lower latency for your users and the peace of mind of knowing that you can survive regional outages.
 ">
   <meta name="keywords" content="cassandra, apache, apache cassandra, distributed storage, key value store, scalability, bigtable, dynamo" />
   <meta name="robots" content="index,follow" />
   <meta name="language" content="en" />

   <title>Documentation</title>

   <link rel="canonical" href="http://cassandra.apache.org/doc/4.0-alpha4/operating/compaction/stcs.html">

   <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" integrity="sha384-1q8mTJOASx8j1Au+a5WDVnPi2lkFfwwEAa8hDDdjZlpLegxhjVME1fgjWPGmkzs7" crossorigin="anonymous">
   <link rel="stylesheet" href="./../../../../css/style.css">

   <link rel="stylesheet" href="./../../../../css/sphinx.css">


    <link rel="top" title="Apache Cassandra Documentation v4.0-alpha4" href="../../index.html"/>
   <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.2.0/css/all.css" integrity="sha384-hWVjflwFxL6sNzntih27bfxkr27PmbbK/iSvJ+a4+0owXq79v+lsFkW54bOGbiDQ" crossorigin="anonymous">

   <link type="application/atom+xml" rel="alternate" href="http://cassandra.apache.org/feed.xml" title="Apache Cassandra Website" />
 </head>

   <body>
     <!-- breadcrumbs -->
 <div class="topnav">
   <div class="container breadcrumb-container">
     <ul class="breadcrumb">
       <li>
         <div class="dropdown">
           <img class="asf-logo" src="./../../../../img/asf_feather.png" />
           <a data-toggle="dropdown" href="#">Apache Software Foundation <span class="caret"></span></a>
           <ul class="dropdown-menu" role="menu" aria-labelledby="dLabel">
             <li><a href="http://www.apache.org">Apache Homepage</a></li>
             <li><a href="http://www.apache.org/licenses/">License</a></li>
             <li><a href="http://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li>
             <li><a href="http://www.apache.org/foundation/thanks.html">Thanks</a></li>
             <li><a href="http://www.apache.org/security/">Security</a></li>
           </ul>
         </div>
       </li>


       <li><a href="./../../../../">Apache Cassandra</a></li>


         <li><a href="./../../../../doc/latest/">Documentation</a></li>


       <li>Leveled Compaction Strategy</li>

     </ul>
   </div>

   <!-- navbar -->
   <nav class="navbar navbar-default navbar-static-top" role="navigation">
     <div class="container">
       <div class="navbar-header">
         <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#cassandra-menu" aria-expanded="false">
           <span class="sr-only">Toggle navigation</span>
           <span class="icon-bar"></span>
           <span class="icon-bar"></span>
           <span class="icon-bar"></span>
         </button>
         <a class="navbar-brand" href="./../../../../"><img src="./../../../../img/cassandra_logo.png" alt="Apache Cassandra logo" /></a>
       </div><!-- /.navbar-header -->

       <div id="cassandra-menu" class="collapse navbar-collapse">
         <ul class="nav navbar-nav navbar-right">
           <li><a href="./../../../../">Home</a></li>
           <li><a href="./../../../../download/">Download</a></li>
           <li><a href="./../../../../doc/latest/">Documentation</a></li>
           <li><a href="./../../../../community/">Community</a></li>
           <li>
             <a href="./../../../../blog/">Blog</a>
         </li>
         </ul>
       </div><!-- /#cassandra-menu -->


     </div>
   </nav><!-- /.navbar -->
 </div><!-- /.topnav -->

     <div class="container-fluid">
   <div class="row">
     <div class="col-md-3">
       <div class="doc-navigation">
         <div class="doc-menu" role="navigation">
           <div class="navbar-header">
             <button type="button" class="pull-left navbar-toggle" data-toggle="collapse" data-target=".sidebar-navbar-collapse">
               <span class="sr-only">Toggle navigation</span>
               <span class="icon-bar"></span>
               <span class="icon-bar"></span>
               <span class="icon-bar"></span>
             </button>
           </div>
           <div class="navbar-collapse collapse sidebar-navbar-collapse">
             <form id="doc-search-form" class="navbar-form" action="../../search.html" method="get" role="search">
               <div class="form-group">
                 <input type="text" size="30" class="form-control input-sm" name="q" placeholder="Search docs">
                 <input type="hidden" name="check_keywords" value="yes" />
                 <input type="hidden" name="area" value="default" />
               </div>
             </form>


             <ul>
 <li class="toctree-l1"><a class="reference internal" href="../../getting_started/index.html">Getting Started</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../new/index.html">New Features in Apache Cassandra 4.0</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../architecture/index.html">Architecture</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../cql/index.html">The Cassandra Query Language (CQL)</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../data_modeling/index.html">Data Modeling</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../configuration/index.html">Configuring Cassandra</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../index.html">Operating Cassandra</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../tools/index.html">Cassandra Tools</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../troubleshooting/index.html">Troubleshooting</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../development/index.html">Contributing to Cassandra</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../faq/index.html">Frequently Asked Questions</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../plugins/index.html">Third-Party Plugins</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../bugs.html">Reporting Bugs</a></li>
 <li class="toctree-l1"><a class="reference internal" href="../../contactus.html">Contact us</a></li>
 </ul>


           </div><!--/.nav-collapse -->
         </div>
       </div>
     </div>
     <div class="col-md-8">
       <div class="content doc-content">
         <div class="content-container">

   <div class="section" id="leveled-compaction-strategy">
 <span id="stcs"></span><h1>Leveled Compaction Strategy<a class="headerlink" href="#leveled-compaction-strategy" title="Permalink to this headline">¶</a></h1>
 <p>The basic idea of <code class="docutils literal notranslate"><span class="pre">SizeTieredCompactionStrategy</span></code> (STCS) is to merge sstables of approximately the same size. All
 sstables are put in different buckets depending on their size. An sstable is added to the bucket if size of the sstable
 is within <code class="docutils literal notranslate"><span class="pre">bucket_low</span></code> and <code class="docutils literal notranslate"><span class="pre">bucket_high</span></code> of the current average size of the sstables already in the bucket. This
 will create several buckets and the most interesting of those buckets will be compacted. The most interesting one is
 decided by figuring out which bucket’s sstables takes the most reads.</p>
 <div class="section" id="major-compaction">
 <h2>Major compaction<a class="headerlink" href="#major-compaction" title="Permalink to this headline">¶</a></h2>
 <p>When running a major compaction with STCS you will end up with two sstables per data directory (one for repaired data
 and one for unrepaired data). There is also an option (-s) to do a major compaction that splits the output into several
 sstables. The sizes of the sstables are approximately 50%, 25%, 12.5%… of the total size.</p>
 </div>
 <div class="section" id="stcs-options">
 <span id="id1"></span><h2>STCS options<a class="headerlink" href="#stcs-options" title="Permalink to this headline">¶</a></h2>
 <dl class="docutils">
 <dt><code class="docutils literal notranslate"><span class="pre">min_sstable_size</span></code> (default: 50MB)</dt>
 <dd>Sstables smaller than this are put in the same bucket.</dd>
 <dt><code class="docutils literal notranslate"><span class="pre">bucket_low</span></code> (default: 0.5)</dt>
 <dd>How much smaller than the average size of a bucket a sstable should be before not being included in the bucket. That
 is, if <code class="docutils literal notranslate"><span class="pre">bucket_low</span> <span class="pre">*</span> <span class="pre">avg_bucket_size</span> <span class="pre">&lt;</span> <span class="pre">sstable_size</span></code> (and the <code class="docutils literal notranslate"><span class="pre">bucket_high</span></code> condition holds, see below), then
 the sstable is added to the bucket.</dd>
 <dt><code class="docutils literal notranslate"><span class="pre">bucket_high</span></code> (default: 1.5)</dt>
 <dd>How much bigger than the average size of a bucket a sstable should be before not being included in the bucket. That
 is, if <code class="docutils literal notranslate"><span class="pre">sstable_size</span> <span class="pre">&lt;</span> <span class="pre">bucket_high</span> <span class="pre">*</span> <span class="pre">avg_bucket_size</span></code> (and the <code class="docutils literal notranslate"><span class="pre">bucket_low</span></code> condition holds, see above), then
 the sstable is added to the bucket.</dd>
 </dl>
 </div>
 <div class="section" id="defragmentation">
 <h2>Defragmentation<a class="headerlink" href="#defragmentation" title="Permalink to this headline">¶</a></h2>
 <p>Defragmentation is done when many sstables are touched during a read.  The result of the read is put in to the memtable
 so that the next read will not have to touch as many sstables. This can cause writes on a read-only-cluster.</p>
 </div>
 </div>


         </div>
       </div>
     </div>
   </div>
 </div>

     <hr />

 <footer>
   <div class="container">
     <div class="col-md-4 social-blk">
       <span class="social">
         <a href="https://twitter.com/cassandra"
            class="twitter-follow-button"
            data-show-count="false" data-size="large">Follow @cassandra</a>
         <script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script>
         <a href="https://twitter.com/intent/tweet?button_hashtag=cassandra"
            class="twitter-hashtag-button"
            data-size="large"
            data-related="ApacheCassandra">Tweet #cassandra</a>
         <script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script>

       </span>
       <a class="subscribe-rss icon-link" href="/feed.xml" title="Subscribe to Blog via RSS">
           <span><i class="fa fa-rss"></i></span>
       </a>
     </div>

     <div class="col-md-8 trademark">
       <p>&copy; 2016 <a href="http://apache.org">The Apache Software Foundation</a>.
       Apache, the Apache feather logo, and Apache Cassandra are trademarks of The Apache Software Foundation.
       <p>
     </div>
   </div><!-- /.container -->
 </footer>

 <!-- Javascript. Placed here so pages load faster -->
 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
 <script src="./../../../../js/underscore-min.js"></script>
 <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js" integrity="sha384-0mSbJDEHialfmuBBQP6A4Qrprq5OVfW37PRR3j5ELqxss1yVqOtnepnHVP9aJ7xS" crossorigin="anonymous"></script>


 <script src="./../../../../js/doctools.js"></script>
 <script src="./../../../../js/searchtools.js"></script>

  <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT:    "", VERSION:     "", COLLAPSE_INDEX: false, FILE_SUFFIX: ".html", HAS_SOURCE:  false, SOURCELINK_SUFFIX: ".txt" }; </script>


 <script type="text/javascript">
   var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
   document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));

   try {
     var pageTracker = _gat._getTracker("UA-11583863-1");
     pageTracker._trackPageview();
   } catch(err) {}
 </script>


   </body>
 </html>
	<!DOCTYPE html>
	<html>




	<head>
	<meta charset="utf-8">
	<meta http-equiv="X-UA-Compatible" content="IE=edge">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<meta name="description" content="The Apache Cassandra database is the right choice when you need scalability and high availability without compromising performance. Linear scalability and proven fault-tolerance on commodity hardware or cloud infrastructure make it the perfect platform for mission-critical data. Cassandra's support for replicating across multiple datacenters is best-in-class, providing lower latency for your users and the peace of mind of knowing that you can survive regional outages.
	">
	<meta name="keywords" content="cassandra, apache, apache cassandra, distributed storage, key value store, scalability, bigtable, dynamo" />
	<meta name="robots" content="index,follow" />
	<meta name="language" content="en" />

	<title>Documentation</title>

	<link rel="canonical" href="http://cassandra.apache.org/doc/4.0-alpha4/operating/compaction/stcs.html">

	<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" integrity="sha384-1q8mTJOASx8j1Au+a5WDVnPi2lkFfwwEAa8hDDdjZlpLegxhjVME1fgjWPGmkzs7" crossorigin="anonymous">
	<link rel="stylesheet" href="./../../../../css/style.css">

	<link rel="stylesheet" href="./../../../../css/sphinx.css">


	<link rel="top" title="Apache Cassandra Documentation v4.0-alpha4" href="../../index.html"/>
	<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.2.0/css/all.css" integrity="sha384-hWVjflwFxL6sNzntih27bfxkr27PmbbK/iSvJ+a4+0owXq79v+lsFkW54bOGbiDQ" crossorigin="anonymous">

	<link type="application/atom+xml" rel="alternate" href="http://cassandra.apache.org/feed.xml" title="Apache Cassandra Website" />
	</head>

	<body>
	<!-- breadcrumbs -->
	<div class="topnav">
	<div class="container breadcrumb-container">
	<ul class="breadcrumb">
	<li>
	<div class="dropdown">
	<img class="asf-logo" src="./../../../../img/asf_feather.png" />
	<a data-toggle="dropdown" href="#">Apache Software Foundation <span class="caret"></span></a>
	<ul class="dropdown-menu" role="menu" aria-labelledby="dLabel">
	<li><a href="http://www.apache.org">Apache Homepage</a></li>
	<li><a href="http://www.apache.org/licenses/">License</a></li>
	<li><a href="http://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li>
	<li><a href="http://www.apache.org/foundation/thanks.html">Thanks</a></li>
	<li><a href="http://www.apache.org/security/">Security</a></li>
	</ul>
	</div>
	</li>


	<li><a href="./../../../../">Apache Cassandra</a></li>




	<li><a href="./../../../../doc/latest/">Documentation</a></li>






	<li>Leveled Compaction Strategy</li>

	</ul>
	</div>

	<!-- navbar -->
	<nav class="navbar navbar-default navbar-static-top" role="navigation">
	<div class="container">
	<div class="navbar-header">
	<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#cassandra-menu" aria-expanded="false">
	<span class="sr-only">Toggle navigation</span>
	<span class="icon-bar"></span>
	<span class="icon-bar"></span>
	<span class="icon-bar"></span>
	</button>
	<a class="navbar-brand" href="./../../../../"><img src="./../../../../img/cassandra_logo.png" alt="Apache Cassandra logo" /></a>
	</div><!-- /.navbar-header -->

	<div id="cassandra-menu" class="collapse navbar-collapse">
	<ul class="nav navbar-nav navbar-right">
	<li><a href="./../../../../">Home</a></li>
	<li><a href="./../../../../download/">Download</a></li>
	<li><a href="./../../../../doc/latest/">Documentation</a></li>
	<li><a href="./../../../../community/">Community</a></li>
	<li>
	<a href="./../../../../blog/">Blog</a>
	</li>
	</ul>
	</div><!-- /#cassandra-menu -->


	</div>
	</nav><!-- /.navbar -->
	</div><!-- /.topnav -->

	<div class="container-fluid">
	<div class="row">
	<div class="col-md-3">
	<div class="doc-navigation">
	<div class="doc-menu" role="navigation">
	<div class="navbar-header">
	<button type="button" class="pull-left navbar-toggle" data-toggle="collapse" data-target=".sidebar-navbar-collapse">
	<span class="sr-only">Toggle navigation</span>
	<span class="icon-bar"></span>
	<span class="icon-bar"></span>
	<span class="icon-bar"></span>
	</button>
	</div>
	<div class="navbar-collapse collapse sidebar-navbar-collapse">
	<form id="doc-search-form" class="navbar-form" action="../../search.html" method="get" role="search">
	<div class="form-group">
	<input type="text" size="30" class="form-control input-sm" name="q" placeholder="Search docs">
	<input type="hidden" name="check_keywords" value="yes" />
	<input type="hidden" name="area" value="default" />
	</div>
	</form>



	<ul>
	<li class="toctree-l1"><a class="reference internal" href="../../getting_started/index.html">Getting Started</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../new/index.html">New Features in Apache Cassandra 4.0</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../architecture/index.html">Architecture</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../cql/index.html">The Cassandra Query Language (CQL)</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../data_modeling/index.html">Data Modeling</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../configuration/index.html">Configuring Cassandra</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../index.html">Operating Cassandra</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../tools/index.html">Cassandra Tools</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../troubleshooting/index.html">Troubleshooting</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../development/index.html">Contributing to Cassandra</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../faq/index.html">Frequently Asked Questions</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../plugins/index.html">Third-Party Plugins</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../bugs.html">Reporting Bugs</a></li>
	<li class="toctree-l1"><a class="reference internal" href="../../contactus.html">Contact us</a></li>
	</ul>



	</div><!--/.nav-collapse -->
	</div>
	</div>
	</div>
	<div class="col-md-8">
	<div class="content doc-content">
	<div class="content-container">

	<div class="section" id="leveled-compaction-strategy">
	<span id="stcs"></span><h1>Leveled Compaction Strategy<a class="headerlink" href="#leveled-compaction-strategy" title="Permalink to this headline">¶</a></h1>
	<p>The basic idea of <code class="docutils literal notranslate"><span class="pre">SizeTieredCompactionStrategy</span></code> (STCS) is to merge sstables of approximately the same size. All
	sstables are put in different buckets depending on their size. An sstable is added to the bucket if size of the sstable
	is within <code class="docutils literal notranslate"><span class="pre">bucket_low</span></code> and <code class="docutils literal notranslate"><span class="pre">bucket_high</span></code> of the current average size of the sstables already in the bucket. This
	will create several buckets and the most interesting of those buckets will be compacted. The most interesting one is
	decided by figuring out which bucket’s sstables takes the most reads.</p>
	<div class="section" id="major-compaction">
	<h2>Major compaction<a class="headerlink" href="#major-compaction" title="Permalink to this headline">¶</a></h2>
	<p>When running a major compaction with STCS you will end up with two sstables per data directory (one for repaired data
	and one for unrepaired data). There is also an option (-s) to do a major compaction that splits the output into several
	sstables. The sizes of the sstables are approximately 50%, 25%, 12.5%… of the total size.</p>
	</div>
	<div class="section" id="stcs-options">
	<span id="id1"></span><h2>STCS options<a class="headerlink" href="#stcs-options" title="Permalink to this headline">¶</a></h2>
	<dl class="docutils">
	<dt><code class="docutils literal notranslate"><span class="pre">min_sstable_size</span></code> (default: 50MB)</dt>
	<dd>Sstables smaller than this are put in the same bucket.</dd>
	<dt><code class="docutils literal notranslate"><span class="pre">bucket_low</span></code> (default: 0.5)</dt>
	<dd>How much smaller than the average size of a bucket a sstable should be before not being included in the bucket. That
	is, if <code class="docutils literal notranslate"><span class="pre">bucket_low</span> <span class="pre">*</span> <span class="pre">avg_bucket_size</span> <span class="pre"><</span> <span class="pre">sstable_size</span></code> (and the <code class="docutils literal notranslate"><span class="pre">bucket_high</span></code> condition holds, see below), then
	the sstable is added to the bucket.</dd>
	<dt><code class="docutils literal notranslate"><span class="pre">bucket_high</span></code> (default: 1.5)</dt>
	<dd>How much bigger than the average size of a bucket a sstable should be before not being included in the bucket. That
	is, if <code class="docutils literal notranslate"><span class="pre">sstable_size</span> <span class="pre"><</span> <span class="pre">bucket_high</span> <span class="pre">*</span> <span class="pre">avg_bucket_size</span></code> (and the <code class="docutils literal notranslate"><span class="pre">bucket_low</span></code> condition holds, see above), then
	the sstable is added to the bucket.</dd>
	</dl>
	</div>
	<div class="section" id="defragmentation">
	<h2>Defragmentation<a class="headerlink" href="#defragmentation" title="Permalink to this headline">¶</a></h2>
	<p>Defragmentation is done when many sstables are touched during a read. The result of the read is put in to the memtable
	so that the next read will not have to touch as many sstables. This can cause writes on a read-only-cluster.</p>
	</div>
	</div>




	</div>
	</div>
	</div>
	</div>
	</div>

	<hr />

	<footer>
	<div class="container">
	<div class="col-md-4 social-blk">
	<span class="social">
	<a href="https://twitter.com/cassandra"
	class="twitter-follow-button"
	data-show-count="false" data-size="large">Follow @cassandra</a>
	<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script>
	<a href="https://twitter.com/intent/tweet?button_hashtag=cassandra"
	class="twitter-hashtag-button"
	data-size="large"
	data-related="ApacheCassandra">Tweet #cassandra</a>
	<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script>

	</span>
	<a class="subscribe-rss icon-link" href="/feed.xml" title="Subscribe to Blog via RSS">
	<span><i class="fa fa-rss"></i></span>
	</a>
	</div>

	<div class="col-md-8 trademark">
	<p>© 2016 <a href="http://apache.org">The Apache Software Foundation</a>.
	Apache, the Apache feather logo, and Apache Cassandra are trademarks of The Apache Software Foundation.
	<p>
	</div>
	</div><!-- /.container -->
	</footer>

	<!-- Javascript. Placed here so pages load faster -->
	<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
	<script src="./../../../../js/underscore-min.js"></script>
	<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js" integrity="sha384-0mSbJDEHialfmuBBQP6A4Qrprq5OVfW37PRR3j5ELqxss1yVqOtnepnHVP9aJ7xS" crossorigin="anonymous"></script>


	<script src="./../../../../js/doctools.js"></script>
	<script src="./../../../../js/searchtools.js"></script>

	<script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: "", VERSION: "", COLLAPSE_INDEX: false, FILE_SUFFIX: ".html", HAS_SOURCE: false, SOURCELINK_SUFFIX: ".txt" }; </script>



	<script type="text/javascript">
	var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
	document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));

	try {
	var pageTracker = _gat._getTracker("UA-11583863-1");
	pageTracker._trackPageview();
	} catch(err) {}
	</script>


	</body>
	</html>