Examkin

Soru

Zorluk: OrtaCost-Optimized Database Design and Capacity Planning

A startup is launching a mobile fitness tracking application. The application's database must handle write-heavy transaction workloads that are highly unpredictable, with sudden bursts of traffic when popular workouts are shared. The company wants to minimize costs and avoid paying for idle resources, while ensuring no write requests are throttled. Which database configuration should the solutions architect recommend to meet these requirements most cost-effectively?

  1. A
    Use Amazon DynamoDB configured with provisioned capacity mode and enable auto-scaling to adjust capacity based on utilization.
  2. Use Amazon DynamoDB configured with on-demand capacity mode.Cevap
  3. C
    Use Amazon RDS for PostgreSQL with a Multi-AZ deployment and purchase a Compute Savings Plan to reduce compute costs during peak hours.
  4. D
    Use Amazon RDS for MySQL with a Single-AZ deployment and configure an RDS Read Replica as the primary automatic failover target to ensure cost-optimal disaster recovery.

Cevap

Use Amazon DynamoDB configured with on-demand capacity mode.
The correct answer is the option recommending Amazon DynamoDB in on-demand capacity mode. For highly spiky and unpredictable write workloads with idle periods, on-demand capacity mode is the most cost-effective solution. It automatically scales to accommodate the write bursts instantly, ensuring no requests are throttled, and charges only for the request units consumed, resulting in zero cost during idle periods.

Adım Adım Çözüm

1
Analyze the workload characteristics
The workload is characterized by highly unpredictable, spiky write transactions with long idle times.
Understanding the traffic pattern is essential to choosing between provisioned and on-demand database capacities.
2
Evaluate the cost and performance trade-offs of the database engines and capacity modes
Amazon DynamoDB with on-demand capacity mode accommodates instant traffic spikes without throttling and incurs zero cost when there is no traffic.
This step ensures that the recommended solution satisfies both the performance requirement (no throttling) and the cost requirement (no paying for idle resource capacity).
3
Eliminate incorrect cost-saving and database options
Discard options suggesting Compute Savings Plans for RDS (which are unsupported) and reactive auto-scaling or read replica failovers (which fail to handle instant write spikes or high-availability requirements cost-effectively).
Eliminating invalid configurations confirms that the serverless on-demand option is the only structurally sound and cost-optimal recommendation.

Anahtar Kavram

Selecting the cost-optimal database engine and capacity planning strategy for unpredictable, spiky workloads.
Bu soruyu puanla

Konular

Cost-Optimized Database Design and Capacity Planning