AWS Certified Solutions Architect – Associate (SAA-C03)Design Resilient ArchitecturesHard
A software company is developing a new serverless application using AWS Lambda functions. The application needs to store user session data that requires sub-millisecond latency for reads and writes, is frequently accessed, and needs to be highly available and scalable across multiple Availability Zones. The data is non-relational and does not require complex querying capabilities. Which AWS service is the most appropriate for storing this session data?
- AAmazon DynamoDB.
- BAmazon ElastiCache for Redis.
- CAmazon RDS for MySQL.
- DAmazon S3.
Show answer & explanationAnswer & explanation
Correct answer: B. Amazon ElastiCache for Redis.
Amazon ElastiCache for Redis is an in-memory data store that provides sub-millisecond latency for reads and writes, making it ideal for caching and storing frequently accessed session data. It is highly available and scalable, supports clustering across AZs, and is perfectly suited for the low-latency, non-relational needs of a serverless application's session management.
Why the other options are wrong
- A. Amazon DynamoDB offers single-digit millisecond latency, but ElastiCache for Redis provides even faster sub-millisecond latency, which is crucial for high-performance session management.
- C. Amazon RDS is a relational database, not typically used for session data requiring sub-millisecond latency and non-relational access patterns.
- D. Amazon S3 is object storage, suitable for large files and backups, but not for high-speed, sub-millisecond latency reads/writes of session data.
ElastiCache for Redis
A fully managed, in-memory data store service compatible with Redis, providing sub-millisecond latency for data retrieval and storage.
- Ideal for caching, session stores, leaderboards, real-time analytics.
- Supports high availability and horizontal scaling with clustering.
- Offers extremely fast read/write performance.
Memory trick: ElastiCache is the lightning-fast memory desk for your app's short-term thoughts.