Actions to Improve Backup Performance with ElastiCache

Answer: B and C.

Option A is incorrect because rescheduling the backups will not resolve performance issues.

Option B is CORRECT because the reserved-memory-percent parameter specifies the amount of memory available for non-data use.

Setting or increasing this parameter value for cluster nodes can improve performance during backups since more memory will be allocated for the backup processes.

Option C is CORRECT because by performing backups from one of the read replicas, the primary node remains unaffected and can continue serving requests without any performance degradation.

Option D is incorrect because increasing the number of shards increases the number of nodes in a clustered-mode ElastiCache cluster.

It would not improve backup performance.

Option E is incorrect because resharding an ElastiCache means changing the number of nodes in the cluster and performing a redistribution of key spaces.

It would not improve backup performance.

Reference:

https://docs.aws.amazon.com/AmazonElastiCache/latest/red-ug/backups.html#backups-performance

Sure, I'd be happy to explain the options and their potential impact on improving ElastiCache backup performance.

Option A: Schedule automated backup window to occur at midnight. This option involves scheduling the automated backup window to occur at a specific time, in this case, midnight. By doing so, the specialist can potentially reduce the load on the ElastiCache cluster during peak hours, which can improve overall performance. However, this approach assumes that the performance issues are indeed related to the automated backup window and that there are no other underlying issues with the cluster. Additionally, if the application is global, then "midnight" may not be the best time for all users.

Option B: Set the reserved-memory-percent parameter. The reserved-memory-percent parameter reserves a specified percentage of the memory for system processes and overhead, which can help improve performance during heavy workloads. By increasing the reserved-memory-percent parameter, the specialist can potentially allocate more memory to system processes, which can help improve backup performance. However, this approach may also limit the amount of memory available for the cache, which can impact overall performance.

Option C: Create backups from a read replica. Creating backups from a read replica is an option that can help improve performance by offloading the backup process from the primary node. This approach can potentially reduce the impact of backup operations on the primary node, which can help improve overall performance. However, this approach assumes that a read replica is available, and there is sufficient network bandwidth between the primary and the replica to transfer the data.

Option D: Increase the number of shards. Increasing the number of shards can potentially help improve performance by distributing the data across multiple nodes. This approach can potentially reduce the impact of backup operations on a single node and improve overall performance. However, this approach requires additional resources, including memory and CPU, to support additional nodes, which can increase costs.

Option E: Perform a resharding operation. Performing a resharding operation involves redistributing the data across the nodes to balance the load and improve performance. This approach can potentially help improve backup performance by distributing the backup load across multiple nodes. However, this approach can also be complex and time-consuming, and it may require downtime to implement.

In summary, options A, B, and C are potential ways to improve backup performance with minimal impact on the existing architecture. Option D and E, on the other hand, can be more involved and potentially have a more significant impact on the existing architecture and cost. Ultimately, the best approach will depend on the specific requirements, limitations, and resources available to the specialist.