DViewer的专栏

转自：http://hi.baidu.com/_kouu/item/dc8d727b530f40346dc37cd1 在执行一个Job的时候，Hadoop会将输入数据划分成N个Split，然后启动相应的N个Map程序来分别处理它们。 数据如何划分？Split如何调度（如何决定处理Split的Map程序应该运行在哪台TaskTracker机器上）？划分后的数据又如何读取？这就是本文所要讨

I just started to play with Cloudera Manager 5.0.1 and a small fresh setup cluster. It has six datanodes with a total capacity of 16.84 TB, one Namenode and another node for the Cloudera Manager and o

1.  Hadoop+HBase cluster on windows: winutils not found When trying to start hbase from my master (./bin/start-hbase.sh), I get the following error: ....... We've found it. So, in

Number of mappers and reducers can be set like (5 mappers, 2 reducers): -D mapred.map.tasks=5 -D mapred.reduce.tasks=2 in the command line. In the code, one can configure JobConf variables. j

The Java technology that Hive uses to process records and map them to column data types in Hive tables is called SerDe, which is short for SerializerDeserializer. The figure illustrates how SerDes a