Briefing Cloudera Knowledge

How many Mappers will run?

On a cluster running MapReduce v1 (MRv1), a MapReduce job is given a directory of 10 plain text
as its input directory. Each file is made up of 3 HDFS blocks. How many Mappers will run?

A.
We cannot say; the number of Mappers is determined by the developer

B.
30

C.
10

D.
1