SOA-C02 Question 289
Select 2Your company runs an application on Amazon EC2 instances behind an Auto Scaling group. The application experiences varying levels of traffic throughout the day. You have noticed that during periods of low traffic, the application is underutilizing resources, resulting in higher-than-necessary costs. Which of the following actions can be taken to optimize both cost and performance for the application?
- A
Configure a scheduled scaling policy for the Auto Scaling group based on predicted traffic patterns.
- B
Use Spot Instances for the Auto Scaling group to handle the fluctuating traffic.
- C
Switch to Reserved Instances for the Auto Scaling group to minimize costs during low traffic periods.
- D
Enable Auto Scaling instance refresh to automatically replace instances with the latest generation of EC2 instances.
- E
Implement EC2 Auto Scaling with target tracking to adjust the desired capacity dynamically based on a specific utilization metric.
Show answer and explanation
Correct answers: A, E
Explanation
To optimize both cost and performance, leveraging scheduled scaling policies allows for proactive scaling based on predictable traffic patterns, and target tracking scaling policies automatically adjust capacity based on utilization metrics. These approaches ensure the application operates efficiently during varying traffic levels, minimizing costs while maintaining performance.
- A. Correct.
Configuring a scheduled scaling policy based on traffic patterns allows the Auto Scaling group to scale resources up or down in advance, optimizing costs during predictable periods of low traffic.
- B. Incorrect.
Using Spot Instances is cost-effective but not ideal for applications with unpredictable or steady traffic, as Spot Instances can be interrupted at any time, potentially impacting performance.
- C. Incorrect.
Reserved Instances are more suitable for predictable, steady-state workloads rather than applications with varying traffic levels, as they require a long-term commitment.
- D. Incorrect.
Auto Scaling instance refresh is useful for updating the fleet with new instance types or configurations but does not directly address cost optimization for varying traffic levels.
- E. Correct.
Target tracking scaling policies dynamically adjust the Auto Scaling group’s desired capacity based on a metric such as CPU utilization, ensuring performance is maintained while avoiding over-provisioning during low traffic periods.