CloudWatch metrics for DynamoDB - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Read Capacity Units (RCUs) in DynamoDB CloudWatch Metrics

Which CloudWatch metric indicates the number of strongly consistent reads consumed per second by a DynamoDB table?

A ConsumedWriteCapacityUnits

B ConsumedReadCapacityUnits

C ReadThrottleEvents

D WriteThrottleEvents

💡 Hint

Think about the metric that tracks read operations usage.

The ConsumedReadCapacityUnits metric shows the number of read capacity units consumed per second, including strongly consistent reads.

❓ query_result

intermediate

Interpreting Throttling Events from CloudWatch Metrics

If a DynamoDB table's CloudWatch metric WriteThrottleEvents shows a value greater than zero, what does this indicate?

A The table is underutilized and has spare write capacity.

B The table has no write activity.

C The table is experiencing throttling on write requests due to exceeding provisioned capacity.

D The table's read requests are being throttled.

💡 Hint

Focus on what throttling means in DynamoDB context.

WriteThrottleEvents counts the number of write requests that were throttled because the table exceeded its provisioned write capacity.

📝 Syntax

advanced

Correct CloudWatch Metric Name for DynamoDB Table Size

Which of the following is the correct CloudWatch metric name to monitor the total size of a DynamoDB table in bytes?

A TableSizeBytes

B TableSize

C TotalTableSizeBytes

D SizeBytes

💡 Hint

Look for the exact metric name used by AWS CloudWatch for table size.

The correct metric name is TableSizeBytes, which reports the total size of the table in bytes.

❓ optimization

advanced

Optimizing DynamoDB Table Performance Using CloudWatch Metrics

You notice that the ConsumedReadCapacityUnits metric is consistently close to the provisioned read capacity, and ReadThrottleEvents occasionally spikes. What is the best action to reduce throttling?

A Decrease the provisioned read capacity units to save cost.

B Switch to eventually consistent reads to reduce read capacity usage.

C Disable CloudWatch monitoring to reduce overhead.

D Increase the provisioned read capacity units for the table.

💡 Hint

Think about how to handle capacity limits and throttling.

Increasing provisioned read capacity units allows more read requests per second, reducing throttling.

🔧 Debug

expert

Diagnosing Unexpected High Write Capacity Consumption

A DynamoDB table shows unexpectedly high ConsumedWriteCapacityUnits in CloudWatch, but your application writes are low. Which of the following is the most likely cause?

A A large number of small write requests causing inefficient capacity usage.

B The table is being read heavily, causing write capacity to spike.

C The table's read capacity units are being consumed instead.

D CloudWatch metrics are delayed and not accurate.

💡 Hint

Consider how write request size affects capacity consumption.

Many small writes consume more write capacity units inefficiently, causing high ConsumedWriteCapacityUnits despite low write count.