Online Access Free CCD-333 Exam Questions

You have written a Mapper which invokes the following five calls to the outputcollector.collect method:

How many times will the Reducer's reduce method be invoked.

• A.3
• B.0
• C.1
• D.6
• E.5

All keys used for intermediate output from mappers must do which of the following:

• A.Implement WritableComparable
• B.Be a subclass of Filelnput-Format
• C.Override isSplitable
• D.Use a comparator for speedy sorting
• E.Be compressed using a splittable compression algorithm.

In a MapReduce job, you want each of you input files processed by a single map task. How do you configure a MapReduce job so that a single map task processes each input file regardless of how many blocks the input file occupies?

• A.Set the number of mappers equal to the number of input files you want to process.
• B.Write a custom MapRunner that iterates over all key-value pairs in the entire file.
• C.Write a custom FileInputFormat and override the method isSplittable to always return false.
• D.Increase the parameter that controls minimum split size in the job configuration.

Does the MapReduce programming model provide a way for reducers to communicate with each other?

• A.Yes, all reducers can communicate with each other by passing information through the jobconf object.
• B.Yes, reducers can communicate with each other by dispatching intermediate key value pairs that get shuffled to another reduce
• C.No, each reducer runs independently and in isolation.
• D.Yes, reducers running on the same machine can communicate with each other through shared memory, but not reducers on different machines.

Which MapReduce daemon runs on each slave node and participates in job execution?

• A.NameNode
• B.Secondary NameNode
• C.JobTracker
• D.TaskTracker