Architect

Jan 7, 2026 · Databases

Why Did Redis Suddenly Evict Keys? A Deep Dive into Memory, Pipelines, and Client Buffers

This article walks through a production incident where Redis began returning missing keys, detailing the step‑by‑step diagnosis—from monitoring logs and TTL checks to discovering memory spikes caused by client‑output‑buffer‑limit overflow and pipeline traffic—followed by emergency and permanent remediation measures.