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From "nguyenhuynh.mr" <nguyenhuynh...@gmail.com>
Subject Num map task?
Date Wed, 22 Apr 2009 07:35:44 GMT
Hi all!

I have a MR job use to import contents into HBase.

The content is text file in HDFS. I used the maps file to store local
path of contents.

Each content has the map file. ( the map is a text file in HDFS and
contain 1 line info).

I created the maps directory used to contain map files. And the  this
maps directory used to input path for job.

When i run job, the number map task is same number map files.
Ex: I have 5 maps file -> 5 map tasks.

Therefor, the map phase is slowly :(

Why the map phase is slowly if the number map task large and the number
map task is equal number of files?.

* p/s: Run jobs with: 3 node: 1 server and 2 slaver

Please help me!


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