How Redis caching improves web application performance

How to select, expire and invalidate Redis cache entries without showing users stale or incorrect data. This guide explains the practical decisions behind it and what those decisions mean for the people using and operating the product.

Cache expensive repeatable work

Good candidates include stable configuration, catalogue fragments and aggregates requested repeatedly. Per-request work that is already cheap may gain nothing from another network lookup.

Choose keys that reflect scope

Keys should include tenant, user, locale or version where those values change the result. Weak key design can expose the wrong information or make invalidation unreliable.

Set deliberate lifetimes

A time-to-live limits staleness and storage, but not every value should expire on the same schedule. Business tolerance should determine whether seconds, minutes or explicit invalidation is appropriate.

Invalidate when source data changes

Application events can remove or replace affected entries. Broadly clearing the entire cache is easy but can create a sudden database spike and remove unrelated useful data.

Measure the complete effect

Track hit rate, memory, response time and source-database load. A high hit rate is not success if customers receive outdated prices or permissions.

Explore our Redis technology page or discuss the requirement with Noviom Labs.