A company is using Amazon DynamoDB with Auto Scaling enabled. During a flash sale, write traffic spikes and the application experiences ProvisionedThroughputExceededException errors. The DynamoDB table has provisioned write capacity of 1000 WCU and Auto Scaling is set to scale between 1000 and 10000 WCU. What is the most likely cause of the throttling?

Question

Accepted Answer

Auto Scaling cannot react quickly enough to sudden traffic spikes.. DynamoDB Auto Scaling uses a target tracking policy that adjusts capacity based on consumed WCU over a period (typically 5 minutes). During sudden traffic spikes, the consumption increases rapidly, but Auto Scaling cannot react immediately; there is a lag before the scaling policy triggers and additional capacity is provisioned. This results in ProvisionedThroughputExceededException errors until the new capacity takes effect. Option B is incorrect because throttling is due to insufficient write capacity, not partitioning. Option C is incorrect because burst capacity provides a short-term buffer but is quickly exhausted during sustained spikes. Option D is incorrect because the maximum WCU of 10000 is higher than the spike demand, so the limit is not the issue—the timing of the scaling action is the problem.

Answer

The DynamoDB table has insufficient partitions to handle the traffic.

Answer

The table's burst capacity is exhausted and Auto Scaling has not yet increased capacity.

Answer

The Auto Scaling policy has a maximum WCU limit that is too low.

DBS-C01 Management and Operations Practice Question

Why each option matters

Option-by-option breakdown

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