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From 我的Gmail邮箱 <zhangxiang...@gmail.com>
Subject why reduce task can be scheduled before map tasks are 100% completed?
Date Sun, 02 Aug 2009 12:02:24 GMT
Hi, everyone.
In class org.apache.hadoop.mapred.JobInProgress, there is a public method:
scheduleReduces(), it will return true if "finishedMapTasks >=
and then the scheduler can schedule a new reduce task for a given

but as I konw, reduce can not be started unitl map is 100% completed. Does
anyone can explain it? thanks a lot.

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