apache
/
hadoop
miroir de https://github.com/apache/hadoop.git


			
							123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329
							<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta content="Apache Forrest" name="Generator">
<meta name="Forrest-version" content="0.8">
<meta name="Forrest-skin-name" content="pelt">
<title>Welcome to Hadoop!</title>
<link type="text/css" href="skin/basic.css" rel="stylesheet">
<link media="screen" type="text/css" href="skin/screen.css" rel="stylesheet">
<link media="print" type="text/css" href="skin/print.css" rel="stylesheet">
<link type="text/css" href="skin/profile.css" rel="stylesheet">
<script src="skin/getBlank.js" language="javascript" type="text/javascript"></script><script src="skin/getMenu.js" language="javascript" type="text/javascript"></script><script src="skin/fontsize.js" language="javascript" type="text/javascript"></script>
<link rel="shortcut icon" href="images/favicon.ico">
</head>
<body onload="init()">
<script type="text/javascript">ndeSetTextSize();</script>
<div id="top">
<!--+
    |breadtrail
    +-->
<div class="breadtrail">
<a href="http://www.apache.org/">Apache</a> &gt; <a href="http://lucene.apache.org/">Lucene</a> &gt; <a href="http://lucene.apache.org/hadoop/">Hadoop</a><script src="skin/breadcrumbs.js" language="JavaScript" type="text/javascript"></script>
</div>
<!--+
    |header
    +-->
<div class="header">
<!--+
    |start group logo
    +-->
<div class="grouplogo">
<a href="http://lucene.apache.org/"><img class="logoImage" alt="Lucene" src="images/lucene_green_150.gif" title="Apache Lucene"></a>
</div>
<!--+
    |end group logo
    +-->
<!--+
    |start Project Logo
    +-->
<div class="projectlogo">
<a href="http://lucene.apache.org/hadoop/"><img class="logoImage" alt="Hadoop" src="images/hadoop-logo.jpg" title="Scalable Computing Platform"></a>
</div>
<!--+
    |end Project Logo
    +-->
<!--+
    |start Search
    +-->
<div class="searchbox">
<form action="http://www.google.com/search" method="get" class="roundtopsmall">
<input value="lucene.apache.org" name="sitesearch" type="hidden"><input onFocus="getBlank (this, 'Search the site with google');" size="25" name="q" id="query" type="text" value="Search the site with google">&nbsp; 
                    <input name="Search" value="Search" type="submit">
</form>
</div>
<!--+
    |end search
    +-->
<!--+
    |start Tabs
    +-->
<ul id="tabs">
<li class="current">
<a class="selected" href="index.html">Main</a>
</li>
<li>
<a class="unselected" href="http://wiki.apache.org/lucene-hadoop">Wiki</a>
</li>
</ul>
<!--+
    |end Tabs
    +-->
</div>
</div>
<div id="main">
<div id="publishedStrip">
<!--+
    |start Subtabs
    +-->
<div id="level2tabs"></div>
<!--+
    |end Endtabs
    +-->
<script type="text/javascript"><!--
document.write("Last Published: " + document.lastModified);
//  --></script>
</div>
<!--+
    |breadtrail
    +-->
<div class="breadtrail">

             &nbsp;
           </div>
<!--+
    |start Menu, mainarea
    +-->
<!--+
    |start Menu
    +-->
<div id="menu">
<div onclick="SwitchMenu('menu_1.1', 'skin/')" id="menu_1.1Title" class="menutitle">Project</div>
<div id="menu_1.1" class="menuitemgroup">
<div class="menuitem">
<a href="releases.html">Releases</a>
</div>
<div class="menuitem">
<a href="releases.html#News">News</a>
</div>
<div class="menuitem">
<a href="credits.html">Credits</a>
</div>
<div class="menuitem">
<a href="http://www.cafepress.com/hadoop/">Buy Stuff</a>
</div>
</div>
<div onclick="SwitchMenu('menu_1.2', 'skin/')" id="menu_1.2Title" class="menutitle">Documentation</div>
<div id="menu_1.2" class="menuitemgroup">
<div class="menuitem">
<a href="documentation.html">Overview</a>
</div>
<div class="menuitem">
<a href="quickstart.html">Quickstart</a>
</div>
<div class="menuitem">
<a href="cluster_setup.html">Cluster Setup</a>
</div>
<div class="menuitem">
<a href="hdfs_design.html">HDFS Architecture</a>
</div>
<div class="menuitem">
<a href="mapred_tutorial.html">Map-Reduce Tutorial</a>
</div>
<div class="menuitem">
<a href="api/index.html">API Docs</a>
</div>
<div class="menuitem">
<a href="http://wiki.apache.org/lucene-hadoop/">Wiki</a>
</div>
<div class="menuitem">
<a href="http://wiki.apache.org/lucene-hadoop/FAQ">FAQ</a>
</div>
<div class="menuitem">
<a href="mailing_lists.html#Users">Mailing Lists</a>
</div>
</div>
<div onclick="SwitchMenu('menu_1.3', 'skin/')" id="menu_1.3Title" class="menutitle">Developers</div>
<div id="menu_1.3" class="menuitemgroup">
<div class="menuitem">
<a href="mailing_lists.html#Developers">Mailing Lists</a>
</div>
<div class="menuitem">
<a href="issue_tracking.html">Issue Tracking</a>
</div>
<div class="menuitem">
<a href="version_control.html">Version Control</a>
</div>
<div class="menuitem">
<a href="http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Nightly/">Nightly Build</a>
</div>
<div class="menuitem">
<a href="irc.html">IRC Channel</a>
</div>
</div>
<div id="credit">
<hr>
<a href="http://forrest.apache.org/"><img border="0" title="Built with Apache Forrest" alt="Built with Apache Forrest - logo" src="images/built-with-forrest-button.png" style="width: 88px;height: 31px;"></a>
</div>
<div id="roundbottom">
<img style="display: none" class="corner" height="15" width="15" alt="" src="skin/images/rc-b-l-15-1body-2menu-3menu.png"></div>
<!--+
  |alternative credits
  +-->
<div id="credit2"></div>
</div>
<!--+
    |end Menu
    +-->
<!--+
    |start content
    +-->
<div id="content">
<div title="Portable Document Format" class="pdflink">
<a class="dida" href="index.pdf"><img alt="PDF -icon" src="skin/images/pdfdoc.gif" class="skin"><br>
        PDF</a>
</div>
<h1>Welcome to Hadoop!</h1>
<div id="minitoc-area">
<ul class="minitoc">
<li>
<a href="#Getting+Started"> Getting Started </a>
</li>
<li>
<a href="#Getting+Involved"> Getting Involved </a>
</li>
</ul>
</div>
    
<p>
    Hadoop is a software platform that lets one easily write and run
    applications that process vast amounts of data.</p>

    
<p>Here's what makes Hadoop especially useful:</p>
    
<ul>
      
<li>
<strong>Scalable:</strong>
      Hadoop can reliably store and process petabytes.</li>
      
<li>
<strong>Economical:</strong>
      It distributes the data and processing across clusters of
      commonly available computers. These clusters can number into the
      thousands of nodes.</li>
      
<li>
<strong>Efficient:</strong>
      By distributing the data, Hadoop can process it in parallel on
      the nodes where the data is located. This makes it extremely
      rapid.</li>
      
<li>
<strong>Reliable:</strong>
      Hadoop automatically maintains multiple copies of data and
      automatically redeploys computing tasks based on failures.</li>
    
</ul>
    
<p>
    Hadoop implements <a href="http://wiki.apache.org/lucene-hadoop/HadoopMapReduce">MapReduce</a>,
    using the Hadoop Distributed File System (<a href="hdfs_design.html"><acronym title="Hadoop Distributed File System">HDFS</acronym></a>) (see figure below.)  MapReduce divides
    applications into many small blocks of work.  HDFS creates
    multiple replicas of data blocks for reliability, placing them on
    compute nodes around the cluster.  MapReduce can then process the
    data where it is located.
    </p>

    
<p>Hadoop has been demonstrated on clusters with 2000 nodes.
    The current design target is 10,000 node clusters.</p>

    
<p>Hadoop is a <a href="http://lucene.apache.org/">Lucene</a> sub-project
    that contains the distributed computing platform that was
    formerly a part of <a href="http://lucene.apache.org/nutch/">Nutch</a>. 
    </p>

    
<p>For more information about Hadoop, please see the <a href="http://wiki.apache.org/lucene-hadoop/">Hadoop wiki.</a>
</p>     


<div id="" style="text-align: center;">
<img id="" class="figure" alt="architecture" src="images/architecture.gif"></div>

    
<a name="N1004E"></a><a name="Getting+Started"></a>
<h2 class="h3"> Getting Started </h2>
<div class="section">
<p>
      The Hadoop project plans to scale Hadoop up to handling thousands of computers. However, to begin with you can start by installing in on a single machine or a very small cluster.
      </p>
<ol>
        
<li>
<a href="documentation.html">Learn about</a> Hadoop by reading the documentation.</li>
        
<li>
<a href="releases.html">Download</a> Hadoop from the release page.</li>
        
<li>Hadoop <a href="quickstart.html">Quickstart</a>.</li>
        
<li>
<a href="cluster_setup.html">Hadoop Cluster Setup</a>.</li>
        
<li>
<a href="mailing_lists.html">Discuss it</a> on the mailing list.</li>
      
</ol>
</div>

    
<a name="N1007A"></a><a name="Getting+Involved"></a>
<h2 class="h3"> Getting Involved </h2>
<div class="section">
<p>
      Hadoop is an open source volunteer project under the Apache Software Foundation. We encourage you to learn about the project and contribute your expertise. Here are some starter links:
      </p>
<ol>
        
<li>See our <a href="http://wiki.apache.org/lucene-hadoop/HowToContribute">How to Contribute to Hadoop</a> page.</li>
        
<li>Give us <a href="issue_tracking.html">feedback</a>: What can we do better?</li>
        
<li>Join the <a href="mailing_lists.html">mailing list</a>: Meet the community.</li>
      
</ol>
</div>

  
</div>
<!--+
    |end content
    +-->
<div class="clearboth">&nbsp;</div>
</div>
<div id="footer">
<!--+
    |start bottomstrip
    +-->
<div class="lastmodified">
<script type="text/javascript"><!--
document.write("Last Published: " + document.lastModified);
//  --></script>
</div>
<div class="copyright">
        Copyright &copy;
         2007 <a href="http://www.apache.org/licenses/">The Apache Software Foundation.</a>
</div>
<div id="logos"></div>
<!--+
    |end bottomstrip
    +-->
</div>
</body>
</html>