DBS-C01 Management and Operations Practice Question
A social media company runs a large Amazon DynamoDB table (Users) with 10 TB of data. The table uses on-demand capacity. Recently, the application started experiencing occasional ProvisionedThroughputExceeded exceptions during read-heavy periods. The table's read metrics show that consumed read capacity is consistently below 50% of provisioned capacity. The application uses eventually consistent reads. The table has a global secondary index (GSI) on the 'status' attribute. The GSI's read capacity consumption is often at 100% of its provisioned capacity. What is the most likely cause of the throttling?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The GSI is throttling because its read capacity is not set to on-demand, or the GSI's partition key is causing hot partitions.
The GSI has its own read capacity settings. If the GSI is throttled, reads on the base table that require the GSI may also be throttled. Option C is correct because the GSI is likely using provisioned capacity, not on-demand, and its read capacity is often at 100%, causing throttling. Option A is incorrect because on-demand capacity mode for the base table is not the issue; the issue is the GSI. Option B is incorrect because the base table's read capacity is not the bottleneck (consumed read capacity is below 50%). Option D is incorrect because using strongly consistent reads would increase read consumption, not reduce throttling.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The on-demand capacity mode is not suitable for this workload; switch to provisioned with auto scaling.
Why it's wrong here
On-demand is suitable; the issue is with the GSI.
- ✗
The base table's read capacity is insufficient despite on-demand mode.
Why it's wrong here
On-demand mode does not have provisioned capacity limits; it throttles only on partition limits.
- ✓
The GSI is throttling because its read capacity is not set to on-demand, or the GSI's partition key is causing hot partitions.
Why this is correct
GSI has its own capacity; if it throttles, base table reads that use the GSI may be throttled.
- ✗
The application should use strongly consistent reads to reduce throttling.
Why it's wrong here
Strongly consistent reads consume more capacity, not less.
Go deeper
Related to this question
About these practice questions
This DBS-C01 question is part of Courseiva's 1,663-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DBS-C01 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DBS-C01 exam.