An Online Advertising Website Uses an Amazon DynamoDB Table with On-Demand

question 149

Multiple Choice

An online advertising website uses an Amazon DynamoDB table with on-demand capacity mode as its data store. The website also has a DynamoDB Accelerator (DAX) cluster in the same VPC as its web application server. The application needs to perform infrequent writes and many strongly consistent reads from the data store by querying the DAX cluster. During a performance audit, a systems administrator notices that the application can look up items by using the DAX cluster. However, the QueryCacheHits metric for the DAX cluster consistently shows 0 while the QueryCacheMisses metric continuously keeps growing in Amazon CloudWatch. What is the MOST likely reason for this occurrence?

• A) A VPC endpoint was not added to access DynamoDB.
• B) Strongly consistent reads are always passed through DAX to DynamoDB.
• C) DynamoDB is scaling due to a burst in traffic, resulting in degraded performance.
• D) A VPC endpoint was not added to access CloudWatch.

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Definitions:

Phenotype

Set of individual characteristics that can be seen or measured.

Puberty

The period in human development during which adolescents undergo physical changes to reach sexual maturity.

Dopamine

A neurotransmitter involved in many functions, including motivation, reward, reinforcement, motor control, and the regulation of mood.

Hotspots

Areas or regions that are significantly warmer than their surroundings, often referring to places of increased activity or danger in various contexts.