The latest articles on DEV Community by Kendall Ellis (@kendall_codes). https://dev.to/kendall_codes https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4210894%2Fbeb1a156-c24e-4e5a-8235-a76cdd7aab95.jpg https://dev.to/kendall_codes en Kendall Ellis Tue, 27 Oct 2026 15:20:40 +0000 https://dev.to/kendall_codes/why-i-stopped-reaching-for-redis-first-2i9g https://dev.to/kendall_codes/why-i-stopped-reaching-for-redis-first-2i9g <p>Every time a service got slow, my reflex was to add a cache. This week I finally ran the numbers on one of those services and found that the cache was hiding a bad query plan.</p> <p>A quick <code>EXPLAIN ANALYZE</code> showed a sequential scan on a table that had grown 10x. Adding one composite index cut p99 from 900ms to 80ms — no cache needed.</p> <p>Not saying Redis is bad (it's great, and we still use it). The lesson is just: measure before caching.</p> <p>We're on Postgres 16 now, and the planner has been excellent once the statistics are fresh. Curious how others handle index review — manual, or automated in CI?</p> postgres database performance