Win a copy of Android Programming: The Big Nerd Ranch Guide this week in the Android forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic

Hadoop - One Map and many Reduces  RSS feed

Luan Cestari
Ranch Hand
Posts: 172
C++ Redhat Ruby
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi Chuck Lam,

Suppose I have some data and I want process it iteratively grouping for a different key. I think this could be done by running some Hadoop Tasks, but each would have an initial load, that is the initial I/O and the mapping process.
My idea was a map once and then do several reduces. Those reduces would emit new maps for the next reduces.
Is it possible to do with Hadoop? What do you think about this approach?

Is there any planning to change the hadoop to run many reduces from the same map? ( I guess then way it is now it can't)

IMO, it look like that if you can do many reduces taking advantage of it is already in the memory would make the process faster than do many jobs with the same map.
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!