What is a Writable?
What is a Writable?
which node will Hadoop first attempt to run the Map task?
You are running a job that will process a single InputSplit on a cluster which has no other jobs
currently running. Each node has an equal number of open Map slots. On which node will Hadoop
first attempt to run the Map task?
Calling the next () method:
In the reducer, the MapReduce API provides you with an iterator over Writable values. Calling the
next () method:
The NameNode uses RAM for the following purpose:
The NameNode uses RAM for the following purpose:
How many keys will be passed to the reducer?
You have the following key value pairs as output from your Map task:
(The, 1)
(Fox, 1)
(Runs, 1)
(Faster, 1)
(Than, 1)
(The, 1)
(Dog, 1)
How many keys will be passed to the reducer?
All keys used for intermediate output from mappers must do which of the following:
All keys used for intermediate output from mappers must do which of the following:
Which statement is most accurate about the ordering of these values?
In a MapReduce job, the reducer receives all values associated with the same key. Which
statement is most accurate about the ordering of these values?
What is the behavior of the default partitioner?
What is the behavior of the default partitioner?
Which of the following is true?
During the standard sort and shuffle phase of MapReduce, keys and values are passed to
reducers. Which of the following is true?
For each input key-value pair, mappers can emit:
For each input key-value pair, mappers can emit: