Hadoop 2.x(YARN)安装配置LZO

今天尝试在Hadoop 2.x(YARN)上安装和配置LZO，遇到了很多坑，网上的资料都是基于Hadoop 1.x的，基本没有对于Hadoop 2.x上应用LZO，我在这边记录整个安装配置过程

1. 安装LZO

下载lzo 2.06版本，编译64位版本，同步到集群中

wget http://www.oberhumer.com/opensource/lzo/download/lzo-2.06.tar.gz
export CFLAGS=-m64
./configure -enable-shared -prefix=/usr/local/hadoop/lzo/
make && make test && make install

同步 /usr/local/hadoop/lzo/到整个集群上

2. 安装Hadoop-LZO

注意，Hadoop 1.x的时候我们是直接按照cloudera的文档clone https://github.com/kevinweil/hadoop-lzo.git上编译的，它是fork自https://github.com/twitter/hadoop-lzo。

但是kevinweil这个版本已经很久没有更新了，而且它是基于Hadoop 1.x去编译的，不能用于Hadoop 2.x。而twitter/hadoop-lzo三个月将Ant的编译方式切换为Maven，默认的dependency中Hadoop jar包就是2.x的，所以要clone twitter的hadoop-lzo，用Maven编译jar包和native library。

编译前先想pom中的hadoop-common和hadoop-mapreduce-client-core版本号改成2.1.0-beta

git clone https://github.com/twitter/hadoop-lzo.git​
export CFLAGS=-m64
export CXXFLAGS=-m64
export C_INCLUDE_PATH=/usr/local/hadoop/lzo/include
export LIBRARY_PATH=/usr/local/hadoop/lzo/lib
mvn clean package -Dmaven.test.skip=true
tar -cBf - -C target/native/Linux-amd64-64/lib . | tar -xBvf - -C /usr/local/hadoop/hadoop-2.1.0-beta/lib/native/
cp target/hadoop-lzo-0.4.18-SNAPSHOT.jar /usr/local/hadoop/hadoop-2.1.0-beta/share/hadoop/common/

lib/native下的文件，包含native libraries和native compression

-rw-r--r-- 1 hadoop hadoop  104206 Sep  2 10:44 libgplcompression.a
-rw-rw-r-- 1 hadoop hadoop    1121 Sep  2 10:44 libgplcompression.la
lrwxrwxrwx 1 hadoop hadoop      26 Sep  2 10:47 libgplcompression.so -> libgplcompression.so.0.0.0
lrwxrwxrwx 1 hadoop hadoop      26 Sep  2 10:47 libgplcompression.so.0 -> libgplcompression.so.0.0.0
-rwxrwxr-x 1 hadoop hadoop   67833 Sep  2 10:44 libgplcompression.so.0.0.0
-rw-rw-r-- 1 hadoop hadoop  835968 Aug 29 17:12 libhadoop.a
-rw-rw-r-- 1 hadoop hadoop 1482132 Aug 29 17:12 libhadooppipes.a
lrwxrwxrwx 1 hadoop hadoop      18 Aug 29 17:12 libhadoop.so -> libhadoop.so.1.0.0
-rwxrwxr-x 1 hadoop hadoop  465801 Aug 29 17:12 libhadoop.so.1.0.0
-rw-rw-r-- 1 hadoop hadoop  580384 Aug 29 17:12 libhadooputils.a
-rw-rw-r-- 1 hadoop hadoop  273642 Aug 29 17:12 libhdfs.a
lrwxrwxrwx 1 hadoop hadoop      16 Aug 29 17:12 libhdfs.so -> libhdfs.so.0.0.0
-rwxrwxr-x 1 hadoop hadoop  181171 Aug 29 17:12 libhdfs.so.0.0.0

将 hadoop-lzo-0.4.18-SNAPSHOT.jar和/usr/local/hadoop/hadoop-2.1.0-beta/lib/native/ 同步到整个集群中

3. 设置环境变量

在hadoop-env.sh中加入

export LD_LIBRARY_PATH=/usr/local/hadoop/lzo/lib

core-site加入

<property>
	<name>io.compression.codecs</name>	<value>org.apache.hadoop.io.compress.GzipCodec,org.apache.hadoop.io.compress.DefaultCodec,com.hadoop.compression.lzo.LzoCodec,com.hadoop.compression.lzo.LzopCodec,org.apache.hadoop.io.compress.BZip2Codec</value>
</property>
<property>
	<name>io.compression.codec.lzo.class</name>
	<value>com.hadoop.compression.lzo.LzoCodec</value>
</property>

mapred-site.xml加入

<property>
	<name>mapred.compress.map.output</name>
	<value>true</value>
</property>
<property>
	<name>mapred.map.output.compression.codec</name>
	<value>com.hadoop.compression.lzo.LzoCodec</value>
</property>
<property>
	<name>mapred.child.env</name>
	<value>LD_LIBRARY_PATH=/usr/local/hadoop/lzo/lib</value>
</property>

其中mapred-site中设置mapred.child.env的 LD_LIBRARY_PATH很重要，因为hadoop-lzo通过JNI调用(java.library.path) libgplcompression.so，然后libgplcompression.so 再通过dlopen这个系统调用（其实是查找系统环境变量LD_LIBRARY_PATH ）来加载liblzo2.so 。container在启动的时候，需要设置LD_LIBRARY_PATH 环境变量，来让LzoCodec加载 native-lzo library，如果不设置的话，会在container的syslog中报下面的错误

2013-09-02 11:20:12,004 INFO [main] com.hadoop.compression.lzo.GPLNativeCodeLoader: Loaded native gpl library
2013-09-02 11:20:12,006 WARN [main] com.hadoop.compression.lzo.LzoCompressor: java.lang.UnsatisfiedLinkError: Cannot load liblzo2.so.2 (liblzo2.so.2: cannot open shared object file: No such file or directory)!
2013-09-02 11:20:12,006 ERROR [main] com.hadoop.compression.lzo.LzoCodec: Failed to load/initialize native-lzo library

同步hadoop-env.sh, core-site.xml, mapred-site.xml到集群

LzoCodec加载gplcompression和lzo native library

  static {
    if (GPLNativeCodeLoader.isNativeCodeLoaded()) {
      nativeLzoLoaded = LzoCompressor.isNativeLzoLoaded() &&
      LzoDecompressor.isNativeLzoLoaded();

      if (nativeLzoLoaded) {
        LOG.info("Successfully loaded & initialized native-lzo library [hadoop-lzo rev " + getRevisionHash() + "]");
      } else {
        LOG.error("Failed to load/initialize native-lzo library");
      }
    } else {
      LOG.error("Cannot load native-lzo without native-hadoop");
    }
  }

LzoCompressor和LzoDecompressor会调用本地方法initIDs

在impl/lzo/LzoCompressor.c中加载liblzo2.so

Java_com_hadoop_compression_lzo_LzoCompressor_initIDs(
  JNIEnv *env, jclass class
  ) {
  // Load liblzo2.so
  liblzo2 = dlopen(HADOOP_LZO_LIBRARY, RTLD_LAZY | RTLD_GLOBAL);
  if (!liblzo2) {
    char* msg = (char*)malloc(1000);
    snprintf(msg, 1000, "%s (%s)!", "Cannot load " HADOOP_LZO_LIBRARY, dlerror());
    THROW(env, "java/lang/UnsatisfiedLinkError", msg);
    return;
  }

  LzoCompressor_clazz = (*env)->GetStaticFieldID(env, class, "clazz",
                                                 "Ljava/lang/Class;");
  LzoCompressor_finish = (*env)->GetFieldID(env, class, "finish", "Z");
  LzoCompressor_finished = (*env)->GetFieldID(env, class, "finished", "Z");
  LzoCompressor_uncompressedDirectBuf = (*env)->GetFieldID(env, class,
                                                    "uncompressedDirectBuf",
                                                    "Ljava/nio/ByteBuffer;");
  LzoCompressor_uncompressedDirectBufLen = (*env)->GetFieldID(env, class,
                                            "uncompressedDirectBufLen", "I");
  LzoCompressor_compressedDirectBuf = (*env)->GetFieldID(env, class,
                                                        "compressedDirectBuf",
                                                        "Ljava/nio/ByteBuffer;");
  LzoCompressor_directBufferSize = (*env)->GetFieldID(env, class,
                                            "directBufferSize", "I");
  LzoCompressor_lzoCompressor = (*env)->GetFieldID(env, class,
                                          "lzoCompressor", "J");
  LzoCompressor_lzoCompressionLevel = (*env)->GetFieldID(env, class,
                                                "lzoCompressionLevel", "I");
  LzoCompressor_workingMemoryBufLen = (*env)->GetFieldID(env, class,
                                                "workingMemoryBufLen", "I");
  LzoCompressor_workingMemoryBuf = (*env)->GetFieldID(env, class,
                                              "workingMemoryBuf",
                                              "Ljava/nio/ByteBuffer;");

  // record lzo library version
  void* lzo_version_ptr = NULL;
  LOAD_DYNAMIC_SYMBOL(lzo_version_ptr, env, liblzo2, "lzo_version");
  liblzo2_version = (NULL == lzo_version_ptr) ? 0
    : (jint) ((unsigned (__LZO_CDECL *)())lzo_version_ptr)();
}

创建container上下文信息的时候，会读取mapred.child.env作为子进程环境变量的一部分

4. 测试mapreduce读lzo

hive新建一张表lzo_test

CREATE TABLE lzo_test(
 col String
)
STORED AS INPUTFORMAT "com.hadoop.mapred.DeprecatedLzoTextInputFormat"
OUTPUTFORMAT "org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat";

下载lzop工具，load一个lzo文件进lzo_test表中，执行“select * from  lzo_test"和"select count(1) from lzo_test"正确

同时用户可以通过单机作业或者分布式程序生成lzo.index文件

hadoop jar /usr/local/hadoop/hadoop-2.1.0-beta/share/hadoop/common/hadoop-lzo-0.4.18-SNAPSHOT.jar com.hadoop.compression.lzo.DistributedLzoIndexer /user/hive/warehouse/lzo_test/
hadoop jar /usr/local/hadoop/hadoop-2.1.0-beta/share/hadoop/common/hadoop-lzo-0.4.18-SNAPSHOT.jar com.hadoop.compression.lzo.LzoIndexer /user/hive/warehouse/lzo_test/

本文链接http://blog.csdn.net/lalaguozhe/article/details/10912527，转载请注明