Data Warehousing on AWS Training Data Warehousing on AWS: Workload Management 5

Question 1

A Redshift cluster has 5 WLM queues configured with memory percentages of 20%, 20%, 20%, 20%, and 15%. What percentage is left for the default queue?

Accepted Answer

5%

Answer

Total WLM memory must equal 100%; with 95% allocated across five queues (20+20+20+20+15), only 5% remains for the default queue.

Question 2

Which feature allows Redshift to automatically scale read capacity to handle unpredictable spikes in concurrent users?

Accepted Answer

Concurrency scaling

Answer

Concurrency scaling automatically adds transient read capacity when query queuing occurs, enabling consistent performance during demand spikes without manual intervention.

Question 3

In Redshift WLM, what does the 'queue assignment rules' evaluation order determine?

Accepted Answer

Which queue a query is routed to when multiple queues have matching criteria

Answer

Redshift evaluates WLM queue assignment rules top-to-bottom; a query is assigned to the first queue in configuration order whose user group or query group criteria match.

Question 4

What Redshift WLM configuration approach is recommended by AWS for most workloads as of recent best practices?

Accepted Answer

Automatic WLM with query priorities

Answer

AWS recommends automatic WLM with priority settings because it uses machine learning to dynamically optimize concurrency and memory, reducing the need for manual tuning.

Question 5

Which of the following is a valid use case for setting a WLM query timeout in Redshift?

Accepted Answer

Preventing runaway queries from consuming cluster resources indefinitely

Answer

WLM query timeouts cancel queries that exceed the configured duration, protecting the cluster from runaway queries that would otherwise monopolize resources.

Data Warehousing on AWS Training Practice Test

Data Warehousing on AWS Training Practice Test

Data Warehousing on AWS Training Data Warehousing on AWS: Workload Management 5