Hi,
I have a question about the strategy described by Jonman Chu:
Hadoop will try to split the file according to how it is split up in
the HDFS
use wordcount as example. suppose hadoop is a word in input file.
and block 1 ends with had, block 2 starts with oop, how to
handle this case?
Hi
Follows Cao Haijun's reply:
Suppose we have set 8 map tasks. How does each map know which part of
input file it should process?
在 2008-7-10，上午2:33，Haijun Cao 写道：
Set number of map slots per tasktracker to 8 in order to run 8 map
tasks
on one machine (assuming one tasktracker per
Set number of map slots per tasktracker to 8 in order to run 8 map tasks
on one machine (assuming one tasktracker per machine) at the same time:
property
namemapred.tasktracker.map.tasks.maximum/name
value8/value
descriptionThe maximum number of map tasks that will be run
simultaneously
