Continuous Improvement for Existing Solutions

A financial services company runs a legacy trading API behind an Application Load Balancer (ALB) in a single region. A newly onboarded partner requires that all traffic to the API traverse a small set of static, allowlisted IP addresses through their corporate firewall, and they demand the lowest possible connection latency for high-frequency requests. The current ALB exposes only DNS names, and the partner cannot allowlist DNS names or the ALB's changing IP ranges. The solutions architect must refactor the ingress without rewriting the application, which relies on host-based HTTP routing rules already configured on the ALB. Which approach best satisfies the requirements?

A media company runs a mobile news application backed by a monolithic REST API on EC2 behind an Application Load Balancer. The API aggregates data from three microservices, and mobile clients frequently over-fetch large JSON payloads on cellular networks, driving high data transfer costs and poor perceived performance. Product analytics show that different app screens need different subsets of the same underlying data, and the team also wants to push live breaking-news updates to active users without polling. The company wants to improve performance and reduce redundant data transfer while minimizing custom server infrastructure to maintain. Which refactoring approach best meets these goals?

A data analytics team runs interactive Amazon Athena queries against 8 TB of JSON application logs stored in a single Amazon S3 prefix. Analysts complain that queries scanning a few days of data take several minutes and cost far more than expected because each query scans the entire dataset. The team wants to improve query performance and reduce cost with minimal ongoing operational overhead, while continuing to receive newly ingested logs daily. Which combination of changes best achieves this?

A company runs an internal reporting application on an Aurora MySQL provisioned cluster with two db.r6g.2xlarge instances (writer plus reader). The application is heavily used for about four hours each business day and is nearly idle the rest of the time, including nights and weekends. Finance flags the cluster as one of the highest recurring costs, yet the team must keep the database instantly available whenever a user logs in, and they cannot tolerate the multi-minute delays of stopping and starting the cluster on a schedule. Which change best reduces cost while preserving on-demand responsiveness?

A company runs a reporting platform on an Amazon Aurora PostgreSQL cluster (Standard configuration) that has grown to handle heavy, sustained analytical query loads. The finance team reports that the monthly Aurora bill has become unpredictable and dominated by I/O charges, which now exceed 30% of the total cluster cost. Read query volume is consistently high throughout every billing period. The team wants to reduce and stabilize costs without redesigning the application or changing the database engine. Which action provides the greatest cost improvement?

A retail company runs a customer-facing web application on an Amazon EC2 Auto Scaling group behind an Application Load Balancer. Traffic follows a highly predictable daily pattern: it ramps up sharply every morning at 8:00 AM as customers log in. The team currently uses target tracking scaling based on average CPU utilization, but they observe elevated latency and HTTP 503 errors for the first 10-15 minutes each morning because instances cannot launch and warm up fast enough to meet the sudden demand. Application startup (bootstrapping and cache warming) takes about 6 minutes per instance. The team wants to improve reliability without permanently over-provisioning. What is the MOST effective way to address this?

A company runs a customer-facing payment API on AWS Lambda behind API Gateway. Recent production deployments have twice caused elevated error rates that went unnoticed for several minutes, resulting in failed transactions before engineers manually rolled back. The team uses AWS CodePipeline and CodeDeploy for deployments. Leadership wants future deployments to automatically shift only a small portion of traffic to the new version first, monitor for errors, and roll back automatically if problems are detected — all with minimal custom code. Which approach best meets these requirements?

A company runs 40 workload accounts under AWS Organizations. The central operations team must build unified dashboards and alarms that correlate CloudWatch metrics and logs from all workload accounts without deploying and maintaining custom agents or Lambda functions to copy data between accounts. They also want to minimize ongoing operational overhead. Which approach best meets these requirements?

A media company serves a large catalog of static images and video thumbnails through Amazon CloudFront, backed by an S3 origin in us-east-1. The site has grown into a global audience, and CloudWatch metrics show the origin fetch rate (requests reaching S3) has climbed steadily as viewers in more regions request the same popular assets simultaneously. Finance flags rising S3 GET request charges and data transfer out to CloudFront. The cache TTLs are already tuned appropriately, and the assets rarely change. The team wants to reduce the number of duplicate origin requests for the same objects across CloudFront's many regional edge caches without changing the application or the S3 bucket structure. Which action best improves the cache efficiency and reduces origin load?

A media company serves static assets to global users from an S3 bucket that is currently configured as a public website endpoint fronted by CloudFront. A recent security audit flagged that the bucket allows anonymous public access and that assets can be retrieved directly from the S3 website URL, bypassing CloudFront (and therefore WAF rules and access logging). The team must remediate this exposure so that assets are only reachable through CloudFront, without changing the object keys or breaking existing viewer URLs. Which approach best meets these requirements with the least ongoing operational overhead?

A financial services company has an existing multi-account AWS environment managed under AWS Organizations. The security team currently exports CloudTrail logs from each account into per-account S3 buckets and manually runs Amazon Athena queries whenever they investigate a suspicious API activity. Investigations frequently span multiple accounts and take days because analysts must manually correlate results across dozens of buckets and re-create Athena tables. Leadership wants to improve the security posture by reducing investigation time and enabling ongoing detection of anomalous API behavior with minimal operational overhead. Which approach BEST meets these requirements?

A SaaS company runs a high-traffic order-processing service on ECS Fargate. The operations team wants per-customer and per-API-endpoint latency and error metrics so they can build dashboards and alarms broken down by both dimensions. There are roughly 8,000 active customers and 40 API endpoints. The team initially implemented this by calling the CloudWatch PutMetricData API from the application on every request with custom dimensions, but the monthly CloudWatch bill has grown dramatically and the API is being throttled during peak load. Which approach improves cost and reliability while preserving the ability to query metrics by customer and endpoint?

A SaaS company runs a customer-facing web application behind an Application Load Balancer with an Auto Scaling group of EC2 instances. Support tickets reveal that customers frequently detect broken checkout and login flows before the operations team does. Existing monitoring relies only on ALB target health checks (a TCP check on port 443) and CloudWatch CPU alarms. The team wants to detect user-facing functional failures and latency degradation for critical multi-step workflows proactively, ideally before real users are affected, with minimal application code changes. Which improvement best meets these requirements?

A SaaS company runs a CI/CD pipeline in AWS CodePipeline with a CodeBuild stage that compiles a large monorepo, downloads hundreds of npm and Maven dependencies on every run, and executes a test suite. The build stage now takes 45 minutes, and developers complain that feedback is too slow, delaying releases. Cost is a secondary concern, but the team wants to reduce build duration with minimal changes to the pipeline structure. Which combination of changes will MOST effectively reduce build time?

A media company runs a fleet of EC2 instances behind an Application Load Balancer in an Auto Scaling group. Deployments use AWS CodeDeploy with an in-place deployment strategy that runs configuration scripts on each existing instance during release. Recently, deployments have caused inconsistent runtime state: some instances end up with drifted package versions, and failed deployments leave the fleet in a partially updated state that is difficult to roll back. Operations wants to eliminate configuration drift, guarantee that every instance runs an identical, tested artifact, and enable fast, reliable rollback. Which approach BEST meets these requirements while improving operational excellence?

A financial services company deploys infrastructure to 40 accounts using AWS CloudFormation StackSets triggered from a central AWS CodePipeline. Recently, engineers have been manually modifying deployed resources in the console during incidents, causing configuration drift that later breaks automated deployments. The platform team wants to continuously detect drift, automatically alert the owning team, and block the pipeline from promoting new changes to any account currently in a drifted state — without manually inspecting each account. Which approach best meets these requirements with the least operational overhead?

A company operates 45 accounts under AWS Organizations. The security team must continuously verify that all accounts comply with a set of standardized rules (encrypted EBS volumes, no public S3 buckets, mandatory tags), and automatically remediate violations without manually configuring each account. They want compliance findings aggregated in a central account and the ability to deploy new rules once and have them apply everywhere, including future accounts. Which approach best meets these requirements with the least ongoing operational effort?

A company runs a production DynamoDB table backing an internal reporting application. Usage is highly predictable during business hours (9 AM to 6 PM, Monday to Friday) with steady, well-understood read and write rates, and near-zero traffic outside those windows. The table is currently configured with on-demand capacity mode, and the finance team reports that DynamoDB costs are significantly higher than expected. The solutions architect must reduce cost while maintaining performance during business hours and avoiding throttling. Which approach best meets these requirements?

A SaaS company runs an event-tracking platform on a DynamoDB table that stores hundreds of millions of records. Only the most recent 30 days of data is queried by the live application, but compliance requires that all records be retained for 7 years for occasional audit queries. The table has grown to over 4 TB and storage costs are rising sharply. Audit queries are infrequent, run offline, and can tolerate multi-second latency. The team wants to reduce ongoing DynamoDB storage costs while preserving queryability of historical data. What is the MOST cost-effective approach?

A company runs a stable fleet of 200 EC2 instances across production and staging for a monolithic Java application. The workload has been running unchanged for over a year with predictable steady-state utilization. A FinOps review found average CPU utilization is 12% and memory utilization is 30%, and all instances are billed at On-Demand rates. The Solutions Architect must reduce compute cost with minimal application refactoring while preserving the ability to change instance families over time. Which combination of actions provides the greatest sustained cost reduction with the least operational risk?