CDP (Big Data Science) 3

Question 1

Which consensus algorithm is commonly used by distributed systems like ZooKeeper to achieve leader election and coordination?

Accepted Answer

Paxos

Answer

ZooKeeper uses the ZAB (ZooKeeper Atomic Broadcast) protocol, which is closely based on the Paxos consensus algorithm.

Question 2

In Hadoop MapReduce, what happens during the 'shuffle and sort' phase?

Accepted Answer

Mapper output is transferred to reducers and sorted by key before reduction

Answer

During shuffle and sort, the framework transfers mapper outputs to the appropriate reducers and sorts them by key so each reducer receives all values for a given key.

Question 3

What is a 'hot partition' problem in distributed NoSQL databases?

Accepted Answer

A single partition receiving a disproportionately high volume of read/write requests

Answer

A hot partition occurs when one partition handles significantly more traffic than others, creating a performance bottleneck in the distributed system.

Question 4

Which characteristic of big data refers to the trustworthiness and accuracy of the data collected?

Accepted Answer

Veracity

Answer

Veracity refers to the uncertainty, noise, and reliability of data — ensuring data quality and accuracy in big data systems.

Question 5

In Apache Kafka, what is the role of the 'consumer group'?

Accepted Answer

To allow multiple consumers to share the work of reading a topic's partitions in parallel

Answer

A consumer group allows multiple consumers to each read from a distinct subset of partitions, enabling parallel consumption of a topic.

CDP - Certified Data Professional Practice Test

CDP - Certified Data Professional Practice Test

CDP (Big Data Science) 3