Exam AWS Certified Data Engineer - Associate DEA-C01 topic 1 question 26 discussion

HDFS is not recommended for persistent storage because once a cluster is terminated, all HDFS data is lost. Also, long-running workloads can fill the disk space quickly. Thus, S3 is the best option since it's highly available, durable, and scalable. AWS Graviton-based instances cost up to 20% less than comparable x86-based Amazon EC2 instances: https://aws.amazon.com/ec2/graviton/

Cost effective + high reliability > S3 Gravitation > Low cost

Rule of thumb: pick the AWS in-house solution provided for that service. Graviton is aws processor, and also EMRFS on S3.

s3 no question. Graviton=> Cost-Effectiveness: Graviton instances are ARM-based instances specifically designed for cloud workloads. They offer significant cost savings compared to x86-based instances while delivering comparable or better performance for many Apache Spark workloads. Performance: Graviton instances are optimized for Spark workloads and can deliver the same level of performance as x86-based instances in many cases. Additionally, EMR offers performance-optimized versions of Spark built for Graviton instances.

My answer is BE

A. - AWS recommends using Amazon S3 as a persistent data store for Amazon EMR due to its scalability, durability, and cost-effectiveness. Storing data in HDFS would require managing and maintaining additional infrastructure, which may incur higher costs in terms of storage, management, and scalability compared to using Amazon S3. AWS documentation emphasizes the benefits of integrating Amazon EMR with Amazon S3 for cost optimization and efficiency. D. - While Graviton instances may offer cost savings in certain scenarios, they might not always be the most cost-effective option depending on the specific workload requirements and availability of compatible software. x86-based instances are more commonly supported by a broader range of software and frameworks, which could result in better performance and compatibility in some cases. Additionally, AWS documentation on instance types and pricing can provide insights into the cost-effectiveness of Graviton instances compared to x86-based instances.

B and D.