adplus-dvertising
frame-decoration

Question

In Hadoop MapReduce, when is the output of the reduce() function written to the distributed file system?

a.

After reading the entire input data

b.

During the copy phase

c.

After merging temporary files

d.

As soon as the reduce task starts

Posted under Big Data Computing

Answer: (d).As soon as the reduce task starts Explanation:In Hadoop MapReduce, the output of the reduce() function is written to the distributed file system as soon as the reduce task starts.

Engage with the Community - Add Your Comment

Confused About the Answer? Ask for Details Here.

Know the Explanation? Add it Here.

Q. In Hadoop MapReduce, when is the output of the reduce() function written to the distributed file system?

Similar Questions

Discover Related MCQs

Q. What is the purpose of the copy phase in reduce tasks?

Q. When does a map task write its partial output data to disk?

Q. What is the purpose of the circular memory buffer in a map task?

Q. What is the role of splits in the MapReduce process?

Q. How does HDFS ensure fault tolerance for data blocks?

Q. What is the purpose of the replication factor in HDFS?

Q. What is the default block size in HDFS?

Q. What is the role of the namenode in HDFS?

Q. What is the primary design goal of the Hadoop Distributed File System (HDFS)?

Q. Why does the Hadoop master represent a single point of failure?

Q. What is the default number of map and reduce slots on a tasktracker in Hadoop?

Q. How does the jobtracker divide input data in a Hadoop MapReduce cluster?

Q. In a MapReduce job, what is the unit of work that users submit to the jobtracker?

Q. What is the role of the master node in a Hadoop MapReduce cluster?

Q. What is the primary purpose of the HBase database?

Q. What is the key advantage of Hadoop's distributed file system, HDFS?

Q. How does Skynet handle worker node failures in its MapReduce implementation?

Q. What is the primary language used for writing MapReduce programs in Disco?

Q. Which of the following companies was one of the early adopters of Hadoop, using it to generate their search index?

Q. What does HBase provide, and what is it built on top of?