Cost Optimization Flashcards
7 cards from real AWS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Cost Optimization flashcards as text
A DevOps team runs nightly integration tests on a fleet of EC2 instances that take 2 hours to complete. Which purchasing option minimizes cost for this predictable workload?
Answer: Spot Instances with a defined duration
Spot Instances with a defined duration (now called Spot blocks) are ideal for batch jobs with a known completion time, offering up to 70% savings over On-Demand.
Which AWS CodePipeline configuration reduces cost when multiple source changes happen in quick succession?
Answer: Enable pipeline execution mode set to QUEUED
QUEUED execution mode causes CodePipeline to queue subsequent runs and deduplicate rapid changes, reducing unnecessary pipeline executions and associated costs.
A team stores all CodeBuild build logs and artifacts indefinitely in S3. What is the most cost-effective way to manage this data over time?
Answer: Apply S3 Lifecycle policies to transition old artifacts to S3 Glacier and expire them after 90 days
S3 Lifecycle policies automate transitioning infrequently accessed artifacts to cheaper storage classes and deleting them after a retention period, directly reducing storage costs.
Which strategy best reduces AWS CodeBuild costs for a project with many small, frequent builds?
Answer: Enable CodeBuild caching for dependencies and Docker layers
CodeBuild caching stores downloaded dependencies and Docker layers between builds, significantly reducing build duration and therefore billable build minutes.
A company uses AWS Lambda in its CI/CD pipeline for custom approval logic. Lambda is invoked thousands of times per day. Which configuration change can reduce Lambda costs?
Answer: Right-size Lambda memory using AWS Lambda Power Tuning
AWS Lambda Power Tuning finds the optimal memory setting that balances execution duration and cost, often finding a sweet spot that minimizes total compute cost.
An ECS-based deployment pipeline runs tasks that scale up and down frequently. Which compute option minimizes idle costs while maintaining rapid scaling?
Answer: Fargate Spot for stateless pipeline tasks
Fargate Spot runs ECS tasks on spare AWS capacity at up to 70% discount, and stateless pipeline tasks can handle the possibility of interruption and restart.
A team wants to reduce the cost of storing Docker images used in their CodePipeline deployments. What is the most cost-effective approach?
Answer: Configure ECR Lifecycle Policies to delete untagged and old images automatically
ECR Lifecycle Policies automatically clean up untagged images and old image versions, reducing the total GB stored and lowering ECR storage costs.