You are developing a combiner that takes as input Text keys, IntWritable values, and emits Text keys, IntWritable values. Which interface should your class implement?

A. Combiner

B. Mapper

C. Reducer

D. Reducer

E. Combiner

You want to populate an associative array in order to perform a map-side join. You've decided to put this information in a text file, place that file into the DistributedCache and read it in your Mapper before any records are processed.

Indentify which method in the Mapper you should use to implement code for reading the file and populating the associative array?

A. combine

B. map

C. init

D. configure

To process input key-value pairs, your mapper needs to lead a 512 MB data file in memory. What is the best way to accomplish this?

A. Serialize the data file, insert in it the JobConf object, and read the data into memory in the configure method of the mapper.

B. Place the data file in the DistributedCache and read the data into memory in the map method of the mapper.

C. Place the data file in the DataCache and read the data into memory in the configure method of the mapper.

D. Place the data file in the DistributedCache and read the data into memory in the configure method of the mapper.

You need to create a job that does frequency analysis on input data. You will do this by writing a Mapper that uses TextInputFormat and splits each value (a line of text from an input file) into individual characters. For each one of these characters, you will emit the character as a key and an InputWritable as the value. As this will produce proportionally more intermediate data than input data, which two resources should you expect to be bottlenecks?

A. Processor and network I/O

B. Disk I/O and network I/O

C. Processor and RAM

D. Processor and disk I/O

You want to run Hadoop jobs on your development workstation for testing before you submit them to your production cluster. Which mode of operation in Hadoop allows you to most closely simulate a production cluster while using a single machine?

A. Run all the nodes in your production cluster as virtual machines on your development workstation.

B. Run the hadoop command with the jt local and the fs file:///options.

C. Run the DataNode, TaskTracker, NameNode and JobTracker daemons on a single machine.

D. Run simldooop, the Apache open-source software for simulating Hadoop clusters.