Map Task in MapReduce Framework

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What ensures the availability of data in the MapReduce framework?

Storing data on a single, highly reliable node

Compressing data to reduce storage requirements

Replicating data across multiple nodes (correct)

Encrypting data for secure transmission

Which statement about MapReduce is true?

It is designed for real-time processing of small datasets

It supports shared mutable state across all nodes

It has multiple opportunities for global synchronization

It is less effective for tasks that do not require global coordination (correct)

When is it faster to process data serially on a single processor instead of using MapReduce?

When dealing with large, distributed datasets

When processing a small dataset or individual records (correct)

When performing batch processing tasks

When real-time processing is required

What is a potential disadvantage of using the MapReduce framework?

Significant startup and execution overhead costs Signup and view all the answers

What is a key advantage of the MapReduce framework?

Availability and resilience through data replication Signup and view all the answers

When does global synchronization occur in the MapReduce framework?

After the map phase ends and before the reduce phase begins Signup and view all the answers

What is the key purpose of the 'Shuffle or Sort' phase in MapReduce?

To redistribute data based on output keys from the map function Signup and view all the answers

What is the primary reason for splitting the input data into shards?

To enable massive parallelization in the map phase Signup and view all the answers

In the context of MapReduce, what is the primary responsibility of the master process?

To dispatch jobs to workers and keep track of progress Signup and view all the answers

In the Word Count example using MapReduce, what is the primary function of the map phase?

To tokenize the input text into individual words Signup and view all the answers

What is the primary function of the reduce phase in MapReduce?

To process each group of output data per key in parallel Signup and view all the answers

In the MapReduce architecture, what is the role of a worker process?

To be assigned either a map task or a reduce task Signup and view all the answers

What is the primary function of the Map task in MapReduce?

To parse the input data and generate key-value pairs of interest Signup and view all the answers

How does the partitioning function in the Map task work?

It determines which Reduce worker will process a particular key-value pair Signup and view all the answers

What happens after all the Map workers have completed their tasks?

The master notifies the Reduce workers to start working Signup and view all the answers

What is the first step a Reduce worker performs after being notified by the master?

It contacts every Map worker to get the data for its partition Signup and view all the answers

Why is sorting the key-value pairs necessary in the Reduce phase?

To group together all occurrences of the same key Signup and view all the answers

In the context of the Word Count example, what would be the key-value pairs generated by the Map task?

The key would be the word, and the value would be 1 for each occurrence Signup and view all the answers