Return to Video

Multiple Reducers - Intro to Hadoop and MapReduce

  • 0:00 - 0:03
    So when we have multiple reducers, say these
  • 0:03 - 0:06
    two, and the mapper might output keys apple,
  • 0:06 - 0:10
    banana, carrot and grape. Which keys, will go
  • 0:10 - 0:13
    to the first reducer? Here are some options. Maybe
  • 0:13 - 0:16
    apple and banana go to the first reducer,
  • 0:16 - 0:19
    or apple and carrot, carrot and grape. Or
  • 0:19 - 0:23
    apple and grape, or, we don't know specifically,
  • 0:23 - 0:25
    but they'll be split evenly with each reducer getting
  • 0:25 - 0:29
    two of the keys. Or we don't know, and it's
  • 0:29 - 0:32
    possible that one reducer could get none of the keys.
タイトル:
Multiple Reducers - Intro to Hadoop and MapReduce
概説:

more » « less
Video Language:
English
Team:
Udacity
プロジェクト:
ud617 - Intro to Hadoop and Mapreduce
Duration:
0:33

English subtitles

改訂 Compare revisions