| <!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>Hadoop本地库</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> > <a href="http://hadoop.apache.org/">Hadoop</a> > <a href="http://hadoop.apache.org/core/">Core</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://hadoop.apache.org/"><img class="logoImage" alt="Hadoop" src="images/hadoop-logo.jpg" title="Apache Hadoop"></a> |
| </div> |
| <!--+ |
| |end group logo |
| +--> |
| <!--+ |
| |start Project Logo |
| +--> |
| <div class="projectlogo"> |
| <a href="http://hadoop.apache.org/core/"><img class="logoImage" alt="Hadoop" src="images/core-logo.gif" 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="hadoop.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"> |
| <input name="Search" value="Search" type="submit"> |
| </form> |
| </div> |
| <!--+ |
| |end search |
| +--> |
| <!--+ |
| |start Tabs |
| +--> |
| <ul id="tabs"> |
| <li> |
| <a class="unselected" href="http://hadoop.apache.org/core/">项目</a> |
| </li> |
| <li> |
| <a class="unselected" href="http://wiki.apache.org/hadoop">维基</a> |
| </li> |
| <li class="current"> |
| <a class="selected" href="index.html">Hadoop 0.18文档</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"> |
| |
| |
| </div> |
| <!--+ |
| |start Menu, mainarea |
| +--> |
| <!--+ |
| |start Menu |
| +--> |
| <div id="menu"> |
| <div onclick="SwitchMenu('menu_selected_1.1', 'skin/')" id="menu_selected_1.1Title" class="menutitle" style="background-image: url('skin/images/chapter_open.gif');">文档</div> |
| <div id="menu_selected_1.1" class="selectedmenuitemgroup" style="display: block;"> |
| <div class="menuitem"> |
| <a href="index.html">概述</a> |
| </div> |
| <div class="menuitem"> |
| <a href="quickstart.html">快速入门</a> |
| </div> |
| <div class="menuitem"> |
| <a href="cluster_setup.html">集群搭建</a> |
| </div> |
| <div class="menuitem"> |
| <a href="hdfs_design.html">HDFS构架设计</a> |
| </div> |
| <div class="menuitem"> |
| <a href="hdfs_user_guide.html">HDFS使用指南</a> |
| </div> |
| <div class="menuitem"> |
| <a href="hdfs_permissions_guide.html">HDFS权限指南</a> |
| </div> |
| <div class="menuitem"> |
| <a href="hdfs_quota_admin_guide.html">HDFS配额管理指南</a> |
| </div> |
| <div class="menuitem"> |
| <a href="commands_manual.html">命令手册</a> |
| </div> |
| <div class="menuitem"> |
| <a href="hdfs_shell.html">FS Shell使用指南</a> |
| </div> |
| <div class="menuitem"> |
| <a href="distcp.html">DistCp使用指南</a> |
| </div> |
| <div class="menuitem"> |
| <a href="mapred_tutorial.html">Map-Reduce教程</a> |
| </div> |
| <div class="menupage"> |
| <div class="menupagetitle">Hadoop本地库</div> |
| </div> |
| <div class="menuitem"> |
| <a href="streaming.html">Streaming</a> |
| </div> |
| <div class="menuitem"> |
| <a href="hadoop_archives.html">Hadoop Archives</a> |
| </div> |
| <div class="menuitem"> |
| <a href="hod.html">Hadoop On Demand</a> |
| </div> |
| <div class="menuitem"> |
| <a href="http://hadoop.apache.org/core/docs/r0.18.2/api/index.html">API参考</a> |
| </div> |
| <div class="menuitem"> |
| <a href="http://hadoop.apache.org/core/docs/r0.18.2/jdiff/changes.html">API Changes</a> |
| </div> |
| <div class="menuitem"> |
| <a href="http://wiki.apache.org/hadoop/">维基</a> |
| </div> |
| <div class="menuitem"> |
| <a href="http://wiki.apache.org/hadoop/FAQ">常见问题</a> |
| </div> |
| <div class="menuitem"> |
| <a href="http://hadoop.apache.org/core/mailing_lists.html">邮件列表</a> |
| </div> |
| <div class="menuitem"> |
| <a href="http://hadoop.apache.org/core/docs/r0.18.2/releasenotes.html">发行说明</a> |
| </div> |
| <div class="menuitem"> |
| <a href="http://hadoop.apache.org/core/docs/r0.18.2/changes.html">变更日志</a> |
| </div> |
| </div> |
| <div id="credit"></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="native_libraries.pdf"><img alt="PDF -icon" src="skin/images/pdfdoc.gif" class="skin"><br> |
| PDF</a> |
| </div> |
| <h1>Hadoop本地库</h1> |
| <div id="minitoc-area"> |
| <ul class="minitoc"> |
| <li> |
| <a href="#%E7%9B%AE%E7%9A%84">目的</a> |
| </li> |
| <li> |
| <a href="#%E7%BB%84%E4%BB%B6">组件</a> |
| </li> |
| <li> |
| <a href="#%E4%BD%BF%E7%94%A8%E6%96%B9%E6%B3%95">使用方法</a> |
| </li> |
| <li> |
| <a href="#%E6%94%AF%E6%8C%81%E7%9A%84%E5%B9%B3%E5%8F%B0">支持的平台</a> |
| </li> |
| <li> |
| <a href="#%E6%9E%84%E5%BB%BAHadoop%E6%9C%AC%E5%9C%B0%E5%BA%93">构建Hadoop本地库</a> |
| <ul class="minitoc"> |
| <li> |
| <a href="#%E6%B3%A8%E6%84%8F">注意</a> |
| </li> |
| </ul> |
| </li> |
| <li> |
| <a href="#%E4%BD%BF%E7%94%A8DistributedCache+%E5%8A%A0%E8%BD%BD%E6%9C%AC%E5%9C%B0%E5%BA%93"> 使用DistributedCache 加载本地库</a> |
| </li> |
| </ul> |
| </div> |
| |
| |
| <a name="N1000D"></a><a name="%E7%9B%AE%E7%9A%84"></a> |
| <h2 class="h3">目的</h2> |
| <div class="section"> |
| <p> |
| 鉴于性能问题以及某些Java类库的缺失,对于某些组件,Hadoop提供了自己的本地实现。 |
| 这些组件保存在Hadoop的一个独立的动态链接的库里。这个库在*nix平台上叫<em>libhadoop.so</em>. 本文主要介绍本地库的使用方法以及如何构建本地库。 |
| </p> |
| </div> |
| |
| |
| <a name="N1001A"></a><a name="%E7%BB%84%E4%BB%B6"></a> |
| <h2 class="h3">组件</h2> |
| <div class="section"> |
| <p>Hadoop现在已经有以下 |
| <a href="http://hadoop.apache.org/core/docs/r0.18.2/api/org/apache/hadoop/io/compress/CompressionCodec.html"> |
| compression codecs</a>本地组件:</p> |
| <ul> |
| |
| <li> |
| <a href="http://www.zlib.net/">zlib</a> |
| </li> |
| |
| <li> |
| <a href="http://www.gzip.org/">gzip</a> |
| </li> |
| |
| <li> |
| <a href="http://www.oberhumer.com/opensource/lzo/">lzo</a> |
| </li> |
| |
| </ul> |
| <p>在以上组件中,lzo和gzip压缩编解码器必须使用hadoop本地库才能运行。 |
| </p> |
| </div> |
| |
| |
| <a name="N1003D"></a><a name="%E4%BD%BF%E7%94%A8%E6%96%B9%E6%B3%95"></a> |
| <h2 class="h3">使用方法</h2> |
| <div class="section"> |
| <p>hadoop本地库的用法很简单:</p> |
| <ul> |
| |
| <li> |
| 看一下 |
| <a href="#%E6%94%AF%E6%8C%81%E7%9A%84%E5%B9%B3%E5%8F%B0">支持的平台</a>. |
| </li> |
| |
| <li> |
| |
| <a href="http://hadoop.apache.org/core/releases.html#Download">下载</a> 预构建的32位i386架构的Linux本地hadoop库(可以在hadoop发行版的<span class="codefrag">lib/native</span>目录下找到)或者自己 |
| <a href="#%E6%9E%84%E5%BB%BAHadoop%E6%9C%AC%E5%9C%B0%E5%BA%93">构建</a> 这些库。 |
| </li> |
| |
| <li> |
| 确保你的平台已经安装了<strong>zlib-1.2</strong>以上版本或者<strong>lzo2.0</strong>以上版本的软件包或者两者均已安装(根据你的需要)。 |
| </li> |
| |
| </ul> |
| <p> |
| <span class="codefrag">bin/hadoop</span> 脚本通过系统属性 |
| <em>-Djava.library.path=<path></em>来确认hadoop本地库是否包含在库路径里。</p> |
| <p>检查hadoop日志文件可以查看hadoop库是否正常,正常情况下会看到:</p> |
| <p> |
| |
| <span class="codefrag"> |
| DEBUG util.NativeCodeLoader - Trying to load the custom-built |
| native-hadoop library... |
| </span> |
| <br> |
| |
| <span class="codefrag"> |
| INFO util.NativeCodeLoader - Loaded the native-hadoop library |
| </span> |
| |
| </p> |
| <p>如果出错,会看到:</p> |
| <p> |
| |
| <span class="codefrag"> |
| INFO util.NativeCodeLoader - Unable to load native-hadoop library for |
| your platform... using builtin-java classes where applicable |
| </span> |
| |
| </p> |
| </div> |
| |
| |
| <a name="N10086"></a><a name="%E6%94%AF%E6%8C%81%E7%9A%84%E5%B9%B3%E5%8F%B0"></a> |
| <h2 class="h3">支持的平台</h2> |
| <div class="section"> |
| <p>Hadoop本地库只支持*nix平台,已经广泛使用在GNU/Linux平台上,但是不支持 |
| <a href="http://www.cygwin.com/">Cygwin</a> |
| 和 <a href="http://www.apple.com/macosx">Mac OS X</a>。 |
| </p> |
| <p>已经测试过的GNU/Linux发行版本:</p> |
| <ul> |
| |
| <li> |
| |
| <a href="http://www.redhat.com/rhel/">RHEL4</a>/<a href="http://fedora.redhat.com/">Fedora</a> |
| |
| </li> |
| |
| <li> |
| <a href="http://www.ubuntu.com/">Ubuntu</a> |
| </li> |
| |
| <li> |
| <a href="http://www.gentoo.org/">Gentoo</a> |
| </li> |
| |
| </ul> |
| <p>在上述平台上,32/64位Hadoop本地库分别能和32/64位的jvm一起正常运行。 |
| </p> |
| </div> |
| |
| |
| <a name="N100B6"></a><a name="%E6%9E%84%E5%BB%BAHadoop%E6%9C%AC%E5%9C%B0%E5%BA%93"></a> |
| <h2 class="h3">构建Hadoop本地库</h2> |
| <div class="section"> |
| <p>Hadoop本地库使用 |
| <a href="http://en.wikipedia.org/wiki/ANSI_C">ANSI C</a> 编写,使用GNU autotools工具链 (autoconf, autoheader, automake, autoscan, libtool)构建。也就是说构建hadoop库的平台需要有标准C的编译器和GNU autotools工具链。请参看 |
| <a href="#%E6%94%AF%E6%8C%81%E7%9A%84%E5%B9%B3%E5%8F%B0">支持的平台</a>。</p> |
| <p>你的目标平台上可能会需要的软件包: |
| </p> |
| <ul> |
| |
| <li> |
| C 编译器 (e.g. <a href="http://gcc.gnu.org/">GNU C Compiler</a>) |
| </li> |
| |
| <li> |
| GNU Autools 工具链: |
| <a href="http://www.gnu.org/software/autoconf/">autoconf</a>, |
| <a href="http://www.gnu.org/software/automake/">automake</a>, |
| <a href="http://www.gnu.org/software/libtool/">libtool</a> |
| |
| </li> |
| |
| <li> |
| zlib开发包 (stable version >= 1.2.0) |
| </li> |
| |
| <li> |
| lzo开发包 (stable version >= 2.0) |
| </li> |
| |
| </ul> |
| <p>如果已经满足了上述先决条件,可以使用<span class="codefrag">build.xml</span> |
| 文件,并把其中的<span class="codefrag">compile.native</span>置为 |
| <span class="codefrag">true</span>,这样就可以生成hadoop本地库:</p> |
| <p> |
| <span class="codefrag">$ ant -Dcompile.native=true <target></span> |
| </p> |
| <p>因为不是所有用户都需要Hadoop本地库,所以默认情况下hadoop不生成该库。 |
| </p> |
| <p>你可以在下面的路径查看新生成的hadoop本地库:</p> |
| <p> |
| <span class="codefrag">$ build/native/<platform>/lib</span> |
| </p> |
| <p>其中<platform>是下列系统属性的组合 |
| <span class="codefrag">${os.name}-${os.arch}-${sun.arch.data.model}</span>;例如 |
| Linux-i386-32。</p> |
| <a name="N10109"></a><a name="%E6%B3%A8%E6%84%8F"></a> |
| <h3 class="h4">注意</h3> |
| <ul> |
| |
| <li> |
| 在生成hadoop本地库的目标平台上<strong>必须</strong> 安装了zlib和lzo开发包;但是如果你只希望使用其中一个的话,在部署时,安装其中任何一个都是足够的。 |
| </li> |
| |
| <li> |
| 在目标平台上生成以及部署hadoop本地库时,都需要根据32/64位jvm选取对应的32/64位zlib/lzo软件包。 |
| </li> |
| |
| </ul> |
| </div> |
| <!--DCCOMMENT:diff begin--> |
| |
| <a name="N1011F"></a><a name="%E4%BD%BF%E7%94%A8DistributedCache+%E5%8A%A0%E8%BD%BD%E6%9C%AC%E5%9C%B0%E5%BA%93"></a> |
| <h2 class="h3"> 使用DistributedCache 加载本地库</h2> |
| <div class="section"> |
| <p>用户可以通过 |
| <a href="mapred_tutorial.html#DistributedCache">DistributedCache</a> |
| 加载本地共享库,并<em>分发</em>和建立库文件的<em>符号链接</em>。 |
| </p> |
| <p>这个例子描述了如何分发库文件并在从map/reduce任务中装载库文件。 |
| </p> |
| <ol> |
| |
| <li>首先拷贝库文件到HDFS。<br> |
| |
| <span class="codefrag">bin/hadoop fs -copyFromLocal mylib.so.1 /libraries/mylib.so.1</span> |
| |
| </li> |
| |
| <li>启动作业时包含以下代码:<br> |
| |
| <span class="codefrag"> DistributedCache.createSymlink(conf); </span> |
| <br> |
| |
| <span class="codefrag"> DistributedCache.addCacheFile("hdfs://host:port/libraries/mylib.so.1#mylib.so", conf); |
| </span> |
| |
| </li> |
| |
| <li>map/reduce任务中包含以下代码:<br> |
| |
| <span class="codefrag"> System.loadLibrary("mylib.so"); </span> |
| |
| </li> |
| |
| </ol> |
| </div> |
| |
| </div> |
| <!--+ |
| |end content |
| +--> |
| <div class="clearboth"> </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 © |
| 2007 <a href="http://www.apache.org/licenses/">The Apache Software Foundation.</a> |
| </div> |
| <!--+ |
| |end bottomstrip |
| +--> |
| </div> |
| </body> |
| </html> |