Best Practices for Scaling AWS RDS Instances
Question
Your company is hosting an application in AWS.
The application consists of a set of web servers and AWS RDS.
The application is a read intensive application.
It has been noticed that the response time of the application increases due to the load on the AWS RDS instance.
Which of the following measures can be taken to scale the data tier? (Select TWO.)
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.Answer - A and D.
The AWS documentation mentions the following.
Amazon RDS Read Replicas provide enhanced performance and durability for database (DB) instances.
This replication feature makes it easy to elastically scale out beyond the capacity constraints of a single DB Instance for read-heavy database workloads.
You can create one or more replicas of a given source DB Instance and serve high-volume application read traffic from multiple copies of your data, thereby increasing aggregate read throughput.
Read replicas can also be promoted when needed to become standalone DB instances.
For more information on AWS RDS Read Replica's, please visit the below URL:
https://aws.amazon.com/rds/details/read-replicas/Amazon ElastiCache is a web service that makes it easy to deploy, operate, and scale an in-memory data store or cache in the cloud.
The service improves the performance of web applications by allowing you to retrieve information from fast, managed, in-memory data stores, instead of relying entirely on slower disk-based databases.
For more information on AWS Elastic Cache, please visit the below URL:
https://aws.amazon.com/elasticache/The best measures to scale the data tier of an application hosted on AWS are as follows:
Create an Amazon RDS Read Replica: This option involves creating a replica of the primary RDS instance, which is used for read operations. The replica is kept in sync with the primary instance using asynchronous replication, which ensures that it has the latest data. The Read Replica can be used to offload read operations from the primary instance, which can reduce the load on it and improve response times for read-intensive workloads. The application layer can be configured to direct read queries to the Read Replica. This approach is particularly useful for read-heavy applications, as it allows you to scale out the read operations independently of the primary instance. Option A is therefore correct.
Use ElastiCache in front of your Amazon RDS DB: Amazon ElastiCache is a managed, in-memory caching service that allows you to improve the performance of your applications by reducing the load on your RDS database. By caching frequently accessed data in ElastiCache, you can reduce the number of read queries that need to be directed to the RDS instance, which can reduce its load and improve response times. This approach is particularly useful for read-intensive applications, as it allows you to scale out the read operations independently of the RDS instance. Option D is therefore correct.
Auto Scaling can be used to scale out and scale in the database tier, but this is not an optimal solution for scaling the data tier of an application hosted on AWS. Auto Scaling is typically used to scale instances in response to changes in traffic, but it is not well-suited for scaling a database tier. Scaling a database tier requires careful consideration of the underlying data structure, query patterns, and other factors that can affect performance. Moreover, scaling a database tier can be a complex and error-prone process, which can lead to downtime and data loss if not done correctly. Therefore, option B is not the best solution in this scenario.
SQS is a message queue service that can be used to decouple components of an application, but it is not well-suited for caching database queries. SQS is typically used to decouple application components by allowing them to communicate asynchronously, which can improve the overall performance and reliability of the application. However, using SQS to cache database queries would require a complex architecture that is difficult to manage and maintain. Therefore, option C is not the best solution in this scenario.
In summary, the best measures to scale the data tier of an application hosted on AWS are to create an Amazon RDS Read Replica and use Amazon ElastiCache to cache frequently accessed data. These measures can improve response times for read-intensive workloads and allow you to scale out the read operations independently of the primary RDS instance.
