Exam AWS Certified Solutions Architect - Professional topic 1 question 805 discussion

B. https://aws.amazon.com/blogs/database/building-a-real-time-gaming-leaderboard-with-amazon-elasticache-for-redis/

Question is a about a latency issue with rankings and leaderboard - this is clearly a use case for sorted sets with Redis ES... so B D was correct if the issue was general in all queries and not specific for rankings

Correct B

D A. must refactor coding for Dynamo sdk B. Redis for caching, not for surge in users =>And to do this, you mush add more lines coding to query from DB and commit to redis C. ignore ofcourse D. Easy way, "queries to get" => read sql => add more replicas + rds proxy

D for me, you can't you S3 to perform read/write for game. It's too slow. You need read performance, so D is the best answer

Definitely B, refer to the following link: https://aws.amazon.com/blogs/database/building-a-real-time-gaming-leaderboard-with-amazon-elasticache-for-redis/

D Q: What use cases does RDS Proxy address? Applications with unpredictable workloads: Applications that support highly variable workloads may attempt to open a burst of new database connections. RDS Proxy’s connection governance allows customers to gracefully scale applications dealing with unpredictable workloads by efficiently reusing database connections. First, RDS Proxy enables multiple application connections to share a database connection for efficient use of database resources. Second, RDS Proxy allows customers to maintain predictable database performance by regulating the number of database connections that are opened. Third, RDS Proxy removes unserviceable application requests to preserve overall performance and availability of the application.

B looks good.

D seems more appropriate here. As rank of individual user is sluggish - which cannot be cached for each and every user. RDS Proxy will help with multiple connections over a single connection to DB and thus, better performance for DB also.

C looks good.

B looks more close.