Exam AWS Certified Database - Specialty topic 1 question 81 discussion

ANS: A snapshot is lazy loaded If the volume is accessed where the data is not loaded, the application accessing the volume encounters a higher latency than normal while the data gets loaded

Unlike Aurora - RDS does not have a warm pool of cache (unless its POSTGRES and you are using CCM there - but there is MYSQL). First touch penalty. Can be mitigated with doing a select * from all tables

An active, long-running transaction can slow the process of creating the read replica. We recommend that you wait for long-running transactions to complete before creating a read replica. If you create multiple read replicas in parallel from the same source DB instance, Amazon RDS takes only one snapshot at the start of the first create action. https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html#USER_ReadRepl.Create

Ans: B https://aws.amazon.com/premiumsupport/knowledge-center/rds-mysql-high-replica-lag/ If the replica SQL_THREAD is the source of replication delays, then those delays could be caused by the following: Long-running queries on the primary DB instance Insufficient DB instance class size or storage Parallel queries run on the primary DB instance Binary logs synced to the disk on the replica DB instance Binlog_format on the replica is set to ROW Replica creation lag

https://aws.amazon.com/about-aws/whats-new/2019/11/amazon-ebs-fast-snapshot-restore-eliminates-need-for-prewarming-data-into-volumes-created-snapshots/

Option A.

Ans: A

A is my choice

Yes, it is A

A is correct

Ans A When you spin up a new replica, its EBS volume loads lazily in the background

Yes A is Correct