In the context of optimizing Hadoop applications, ____ plays a significant role in reducing network traffic.
- Data Compression
- Data Encryption
- Data Replication
- Data Serialization
In the context of optimizing Hadoop applications, data compression plays a significant role in reducing network traffic. Compressing data before transferring it between nodes reduces the amount of data that needs to be transmitted, resulting in faster and more efficient data processing in the Hadoop cluster.
_____ is used for scheduling and managing user jobs in a Hadoop cluster.
- JobTracker
- MapReduce
- ResourceManager
- TaskTracker
ResourceManager is used for scheduling and managing user jobs in a Hadoop cluster. It works in conjunction with the NodeManagers to allocate resources and monitor the execution of tasks on the cluster.
For a MapReduce job processing time-sensitive data, what techniques could be employed to ensure faster execution?
- Data Compression
- In-Memory Computation
- Input Splitting
- Speculative Execution
Speculative Execution is a technique employed for time-sensitive data processing in MapReduce. It involves running duplicate tasks on different nodes and using the result from the first one to finish. This helps mitigate delays caused by slow-performing tasks.
____ is a critical component in Hadoop's architecture, ensuring secure authentication and authorization.
- JobTracker
- NodeManager
- ResourceManager
- SecurityManager
SecurityManager is a critical component in Hadoop's architecture, responsible for ensuring secure authentication and authorization within the Hadoop cluster. It plays a crucial role in protecting the integrity and confidentiality of the data.
In Spark, ____ are immutable collections of data items distributed over a cluster.
- Data Blocks
- DataFrames
- DataSets
- Resilient Distributed Datasets (RDDs)
In Spark, Resilient Distributed Datasets (RDDs) are immutable collections of data items distributed over a cluster. RDDs are the fundamental data structure in Spark, providing fault tolerance and parallel processing capabilities.
The ____ in Apache Pig is used for sorting data in a dataset.
- ARRANGE
- GROUP BY
- ORDER BY
- SORT BY
The 'SORT BY' clause in Apache Pig is used for sorting data in a dataset based on one or more fields. It arranges the data in ascending or descending order, providing flexibility in handling sorted data for further processing.
What is the block size used by HDFS for storing data by default?
- 128 MB
- 256 MB
- 512 MB
- 64 MB
The default block size used by Hadoop Distributed File System (HDFS) for storing data is 128 MB. This block size is configurable but is set to 128 MB in many Hadoop distributions as it provides a balance between storage efficiency and parallel processing.
____ is a popular Scala-based tool for interactive data analytics with Hadoop.
- Flink
- Hive
- Pig
- Spark
Spark is a popular Scala-based tool for interactive data analytics with Hadoop. It provides a fast and general-purpose cluster computing framework for big data processing, making it suitable for various data processing tasks.
In a Hadoop cluster, ____ is used to detect and handle the failure of DataNode machines.
- Failover Controller
- NameNode
- NodeManager
- ResourceManager
The Failover Controller in a Hadoop cluster is responsible for detecting and handling the failure of DataNode machines. It ensures that data availability is maintained by redirecting tasks to healthy DataNodes when a failure occurs.
What is the significance of the WAL (Write-Ahead Log) in HBase?
- Ensuring Data Durability
- Load Balancing
- Managing Table Schema
- Reducing Latency
The Write-Ahead Log (WAL) in HBase is significant for ensuring data durability. It records changes to the data store before they are applied, acting as a safeguard in case of system failures. This mechanism enhances the reliability of data and helps in recovering from unexpected incidents.