AWS Performance Optimization: Practical Wins for Faster, Cheaper Apps

Performance and cost on AWS are two sides of the same coin: a faster application usually does less work, and less work costs less. These are the changes that deliver results first on the products we run.

Measure before you tune

Turn on CloudWatch metrics and logs, and add tracing with AWS X-Ray or OpenTelemetry. Find the slowest endpoints and the most expensive resources before changing anything. Optimising without data is guesswork.

Cache aggressively at the edge

• Serve static assets and images through Amazon CloudFront with long cache lifetimes and fingerprinted file names.
• Cache public API responses at CloudFront where data tolerates a few seconds of staleness.
• Compress responses (Brotli or gzip) and serve modern image formats such as WebP and AVIF.

Add an application cache

Repeated database reads are the most common bottleneck we see. Put Amazon ElastiCache (Redis or Valkey) in front of hot queries, session data and computed results, and set sensible expiry times.

Tune the database

• Add indexes for the queries that actually run — check slow query logs and RDS Performance Insights.
• Use read replicas for reporting and read-heavy traffic.
• Use connection pooling (for example RDS Proxy) so traffic spikes do not exhaust connections, especially from Lambda.

Right-size compute

• Review utilisation with AWS Compute Optimizer and downsize instances that idle below 20–30% CPU.
• Consider Graviton (Arm) instances, which often give better price-performance for Node.js, Python and Java workloads.
• Use Auto Scaling so capacity follows demand instead of peak estimates.
• For steady workloads, commit with Savings Plans; for interruptible batch jobs, use Spot Instances.

Go asynchronous

Move slow work — emails, PDF generation, image processing, third-party calls — out of the request path into SQS queues processed by workers or Lambda. Users get faster responses and the system absorbs spikes gracefully.

Watch the bill like a metric

Set AWS Budgets alerts, tag resources by project and environment, and review Cost Explorer monthly. Unused EBS volumes, idle load balancers and forgotten dev environments add up quickly.

Where to start

If you only do three things this month: put CloudFront in front of your app, cache your hottest queries, and right-size your largest instances. Want a performance and cost review of your AWS account? Talk to our team.