Hadoop使用lzo压缩格式

在hadoop中搭建lzo环境:

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

在hadoop-env.sh中

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

将如下配置到 core-site.xml 中：

<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>  

将如下配置到mapred-site.xml中：

<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>